Entering the world of game development with Unity can be an exciting journey filled with creative possibilities. However, as with learning any complex tool, beginners often encounter roadblocks that can slow progress and cause frustration. The team at NKB Playtech has worked with countless new developers and identified patterns in the most common mistakes beginners make when starting with Unity.
This comprehensive guide breaks down these mistakes and provides practical solutions to help new Unity developers overcome these challenges and accelerate their learning process. Whether you’re creating your first game or looking to improve your development workflow, understanding these pitfalls can save you hours of troubleshooting and help you build better games faster.
Performance-Related Mistakes
One of the most critical aspects of game development is performance optimization. Beginners often create games that run perfectly on their development machines but struggle on target devices. Let’s explore the common performance-related mistakes and their solutions.
Using Update() for Everything
The Mistake: Many beginners place all their game logic inside the Update() method, which runs every frame. This approach can quickly lead to performance issues, especially on mobile devices or when many objects are in the scene.
How to Fix It:
The developers at NKB Playtech recommend a more selective approach to using Update():
- Use appropriate event functions: Consider whether code really needs to run every frame. For example, input detection belongs in Update(), but initialization code should go in Start() or Awake().
- Implement time-based checks: For code that needs to run periodically but not every frame:
csharp
private float checkInterval = 0.5f; // Check every half second
private float lastCheckTime = 0f;
void Update()
{
if (Time.time – lastCheckTime > checkInterval)
{
lastCheckTime = Time.time;
// Run your periodic code here
}
}
- Use coroutines for time-delayed operations:
csharp
IEnumerator PerformTaskPeriodically()
{
while (true)
{
// Task code here
yield return new WaitForSeconds(0.5f);
}
}
void Start()
{
StartCoroutine(PerformTaskPeriodically());
}
Inefficient Object Instantiation and Destruction
The Mistake: Creating and destroying objects during gameplay (like bullets, enemies, or particle effects) is resource-intensive and can cause performance spikes and garbage collection issues.
How to Fix It:
Object pooling is a technique that pre-instantiates objects and reuses them instead of constantly creating and destroying them:
- Create an object pool manager:
csharp
public class ObjectPooler : MonoBehaviour
{
public GameObject objectToPool;
public int poolSize = 20;
private List<GameObject> pooledObjects;
void Start()
{
pooledObjects = new List<GameObject>();
for (int i = 0; i < poolSize; i++)
{
GameObject obj = Instantiate(objectToPool);
obj.SetActive(false);
pooledObjects.Add(obj);
}
}
public GameObject GetPooledObject()
{
for (int i = 0; i < pooledObjects.Count; i++)
{
if (!pooledObjects[i].activeInHierarchy)
{
return pooledObjects[i];
}
}
// Optional: expand pool if all objects are in use
return null;
}
}
- Use objects from the pool instead of instantiating:
csharp
void FireBullet()
{
GameObject bullet = objectPooler.GetPooledObject();
if (bullet != null)
{
bullet.transform.position = firePoint.position;
bullet.transform.rotation = firePoint.rotation;
bullet.SetActive(true);
}
}
Overusing GetComponent()
The Mistake: Calling GetComponent<>() repeatedly in Update() methods creates unnecessary performance overhead since component lookups aren’t free.
How to Fix It:
Cache component references during initialization:
csharp
// Inefficient approach
void Update()
{
GetComponent<Rigidbody>().AddForce(Vector3.up);
}
// Efficient approach
private Rigidbody rb;
void Start()
{
rb = GetComponent<Rigidbody>();
}
void Update()
{
rb.AddForce(Vector3.up);
}
Script Organization Mistakes
Code organization can make or break a project, especially as it grows in size and complexity. NKB Playtech has noticed several common mistakes beginners make in organizing their Unity scripts.
Massive MonoBehaviour Classes
The Mistake: Creating enormous script files that handle multiple responsibilities makes code difficult to maintain, debug, and reuse.
How to Fix It:
Follow the Single Responsibility Principle:
- Break down large classes: Each script should ideally handle one aspect of functionality.
- Use composition over inheritance: Instead of creating deep inheritance hierarchies, compose behavior with smaller, focused components:
csharp
// Instead of one massive PlayerController class that does everything
// Create specialized components
public class PlayerMovement : MonoBehaviour { /* Movement code */ }
public class PlayerHealth : MonoBehaviour { /* Health/damage code */ }
public class PlayerInventory : MonoBehaviour { /* Inventory code */ }
// Main PlayerController references these components
public class PlayerController : MonoBehaviour
{
private PlayerMovement movement;
private PlayerHealth health;
private PlayerInventory inventory;
void Awake()
{
movement = GetComponent<PlayerMovement>();
health = GetComponent<PlayerHealth>();
inventory = GetComponent<PlayerInventory>();
}
}
Public Variables Everywhere
The Mistake: Making all variables public for easy access in the Inspector can lead to unintended modifications and makes code more difficult to maintain.
How to Fix It:
Use [SerializeField] and properties for better encapsulation:
csharp
// Avoid this approach
public float playerSpeed;
public int health;
// Better approach
[SerializeField] private float playerSpeed = 5f;
[SerializeField] private int maxHealth = 100;
private int currentHealth;
public int Health
{
get { return currentHealth; }
set {
currentHealth = Mathf.Clamp(value, 0, maxHealth);
// Can trigger events when health changes
if (currentHealth <= 0)
{
Die();
}
}
}
void Start()
{
currentHealth = maxHealth;
}
Hard-Coded Values
The Mistake: Embedding literal values throughout code creates headaches when values need to be adjusted for balancing or adding features.
How to Fix It:
Create a dedicated configuration class or scriptable objects:
csharp
// Create a ScriptableObject for game settings
[CreateAssetMenu(fileName = “GameSettings”, menuName = “Game/Settings”)]
public class GameSettings : ScriptableObject
{
[Header(“Player Stats”)]
public float moveSpeed = 5f;
public float jumpForce = 8f;
public int maxHealth = 100;
[Header(“Enemy Stats”)]
public float enemySpeed = 3f;
public int enemyDamage = 10;
}
// Then reference it in your components
public class PlayerController : MonoBehaviour
{
public GameSettings settings;
private Rigidbody2D rb;
void Start()
{
rb = GetComponent<Rigidbody2D>();
}
void Update()
{
float horizontalInput = Input.GetAxis(“Horizontal”);
Vector2 movement = new Vector2(horizontalInput * settings.moveSpeed, rb.velocity.y);
rb.velocity = movement;
}
}
Unity Interface and Workflow Mistakes
Unity’s interface offers powerful features, but beginners often miss opportunities to streamline their workflow or misuse certain features.
Not Using Prefabs Properly
The Mistake: Creating duplicate objects by copying and pasting in the scene instead of using prefabs, or making changes to prefab instances without updating the original prefab.
How to Fix It:
Master the prefab workflow:
- Create prefabs for reusable objects: Drag objects from the Hierarchy to the Project window to create prefabs.
- Understand prefab variants: For objects that are similar but need specific differences.
- Use nested prefabs: Break down complex objects into smaller prefabs that can be combined.
- Remember to apply changes: When modifying a prefab instance in the scene, click “Apply” to update the original prefab.
The team at NKB Playtech suggests setting up a consistent prefab structure early in development to maintain organization as projects grow.
Ignoring Unity’s Physics System
The Mistake: Many beginners implement custom physics or movement systems when Unity already provides a robust physics engine.
How to Fix It:
Leverage Unity’s built-in physics components:
- Use the appropriate colliders: Choose the simplest collider shape that works for your needs (Box, Sphere, Capsule).
- Configure physics materials: Adjust friction and bounce properties rather than coding these behaviors manually.
- Use rigidbody-based movement for physical objects:
csharp
// Instead of manually updating transform.position
void Update()
{
float moveHorizontal = Input.GetAxis(“Horizontal”);
float moveVertical = Input.GetAxis(“Vertical”);
Vector3 movement = new Vector3(moveHorizontal, 0.0f, moveVertical);
rb.AddForce(movement * speed);
}
Not Understanding the Execution Order
The Mistake: Writing scripts without understanding when different Unity event functions are called can lead to unexpected behaviors.
How to Fix It:
Learn Unity’s execution order and use the appropriate functions:
- Awake(): Use for initialization that doesn’t depend on other objects
- OnEnable(): When an object becomes active
- Start(): After Awake but before the first frame update
- FixedUpdate(): Use for physics calculations (runs at fixed intervals)
- Update(): For most frame-based logic
- LateUpdate(): For operations that should happen after Update (like camera follow)
Asset and Resource Management Mistakes
Poor asset management can lead to bloated builds, long load times, and memory issues. Here are key mistakes to avoid.
Improper Texture Import Settings
The Mistake: Using incorrect texture import settings leads to unnecessarily large game builds and potential memory issues.
How to Fix It:
Optimize texture import settings based on their usage:
- Set appropriate Max Size: Mobile games might use 1024 or 512, while PC games can go higher.
- Choose the right compression format:
- UI elements often work well with “RGBA 32 bit”
- Most textures can use compressed formats like “RGB Compressed DXT1” (for textures without alpha) or “RGBA Compressed DXT5” (with alpha)
- Consider texture shapes:
- Set “Non-Power of 2” to “None” for UI textures
- Set to “ToNearest” for most game textures
NKB Playtech developers emphasize the importance of reviewing texture sizes regularly during development, especially for mobile games where memory is limited.
Audio Import Settings Negligence
The Mistake: Using default audio import settings for all sound files, leading to unnecessarily large file sizes and potential performance issues.
How to Fix It:
Configure audio import settings based on usage:
- For sound effects:
- Set Load Type to “Decompress on Load” for small SFX
- Use “Compressed in Memory” for longer SFX
- Lower the quality (70-80% is often sufficient)
- Consider converting stereo to mono for positional audio
- For background music:
- Use “Streaming” load type
- Appropriate compression (Vorbis/MP3)
- Lower sample rate if appropriate (22050 Hz is often fine for background music)
Project Organization Chaos
The Mistake: Having a disorganized project folder structure makes assets hard to find and increases the chance of name conflicts or duplicate assets.
How to Fix It:
Implement a consistent folder structure from the beginning:
Assets/
├── _Scenes/
├── Animations/
├── Audio/
│ ├── Music/
│ └── SFX/
├── Materials/
├── Models/
├── Prefabs/
├── Resources/ (Use sparingly!)
├── Scripts/
│ ├── Core/
│ ├── Player/
│ ├── Enemies/
│ └── UI/
├── Sprites/
└── Textures/
The NKB Playtech team recommends establishing naming conventions for all assets (e.g., Player_Walk_Animation, Enemy_Zombie_Model) and sticking to them consistently.
Game Design Implementation Mistakes
How you implement game mechanics can significantly impact the player experience and the maintainability of your project.
Using PlayerPrefs for Everything
The Mistake: Using PlayerPrefs as a general data storage solution for game state, inventory items, progress tracking, etc.
How to Fix It:
Use PlayerPrefs appropriately and implement proper saving systems:
- Limit PlayerPrefs to actual preferences:
- Sound/music volume
- Control sensitivity
- Basic settings
- For game data, create a proper save system:
csharp
[System.Serializable]
public class SaveData
{
public int playerLevel;
public float[] playerPosition = new float[3];
public List<string> inventory = new List<string>();
public Dictionary<string, int> questProgress = new Dictionary<string, int>();
}
public class SaveSystem : MonoBehaviour
{
public void SaveGame()
{
SaveData data = new SaveData();
// Populate data from game state
data.playerLevel = PlayerManager.instance.playerLevel;
data.playerPosition = new float[]
{
Player.instance.transform.position.x,
Player.instance.transform.position.y,
Player.instance.transform.position.z
};
// Convert to JSON
string json = JsonUtility.ToJson(data);
// Save to file
File.WriteAllText(Application.persistentDataPath + “/save.json”, json);
}
public void LoadGame()
{
string path = Application.persistentDataPath + “/save.json”;
if (File.Exists(path))
{
string json = File.ReadAllText(path);
SaveData data = JsonUtility.FromJson<SaveData>(json);
// Apply loaded data to game state
PlayerManager.instance.playerLevel = data.playerLevel;
Vector3 position = new Vector3(
data.playerPosition[0],
data.playerPosition[1],
data.playerPosition[2]
);
Player.instance.transform.position = position;
}
}
}
Not Testing on Target Devices
The Mistake: Developing exclusively in the Unity Editor and not testing regularly on target devices, leading to unexpected performance issues or compatibility problems.
How to Fix It:
Implement a consistent testing process:
- Set up device profiles: Configure multiple build targets if developing cross-platform.
- Schedule regular device testing: Test on actual target hardware at least once a week.
- Use Unity’s Remote tools: Unity Remote allows testing some functionality without constant rebuilding.
- Create performance test scenes: Simple scenes that stress test specific aspects of your game.
Conclusion: Learning from Mistakes
Making mistakes is an inevitable part of learning any complex skill, and Unity game development is no exception. The development team at NKB Playtech encourages beginners to view these common mistakes not as failures but as essential learning opportunities that every successful developer has faced and overcome.
By understanding these common pitfalls, new Unity developers can accelerate their learning process and build more robust, efficient, and enjoyable games from the start. Remember that good development practices established early will save countless hours of debugging and refactoring later in the project lifecycle.
When in doubt, the Unity community offers extensive resources, tutorials, and forums where developers can seek guidance. Additionally, experienced teams like those at NKB Playtech can provide professional support and development services to help bring game ideas to life.
Armed with this knowledge, beginners can approach their Unity projects with greater confidence and avoid the frustrating roadblocks that might otherwise slow their progress.