The opposite also applies: don't reinvent the wheel if you want to get something done.
Existing game engines like Unity/Unreal already have builtin solutions for entity management, but if you're (for whatever reason) using something that's more custom you can avoid having to reinvent entity management by using an ECS library. Similar to how you'd use libraries like SDL/bgfx/sokol for graphics.
Existing game engines like Unity/Unreal already have builtin solutions for entity management, but if you're (for whatever reason) using something that's more custom you can avoid having to reinvent entity management by using an ECS library. Similar to how you'd use libraries like SDL/bgfx/sokol for graphics.