Why Unity3D Sucks

Unity is a great game engine, but it's not perfect.

📌 Unity is limited to C#, thus it's harder to optimize code and memory allocations.
📌 It's not suited for a large open world, AAA games.
📌 Unity is a CPU hog on mobile devices, thus drains the battery quickly.
📌 The code is not open source and you can't make custom engine modifications.
📌 Garbage collection can slow down your game and many engine methods allocate on the heap.
📌 Asset Store is saturated with poorly designed assets.
📌 It still has many performance "gotchas."
📌 Terrain editor and other tools aren't as powerful as competitors, e.g. Unreal engine.
📌 Asset import and reimport times are long (this is a tad better now with asset database v2).
📌 Large projects are slow to open, modify, and compile.
📌 It can be expensive compared to some of the competitors, Unreal and Godot.
⚰️ Prefab conflicts will destroy your soul.

🚀 After many years of professional development with Unity, it is still my preferred engine for most mobile and indie games. I long for more optimization control in code, ❤️ C++, but the toolset for Unity is perfect for rapidly building my mobile and indie games.

🔥 Unity is not perfect, but has improved greatly and will continue to improve in the future. 

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