(For those who don't know, BGE stands for Blender Game Engine. Yes, Blender has a game engine!)
Hey SolarLune! The short answer: Blender is the tool I know the most when it comes to game creation.
Long answer: For my last game I wanted something in 3D so I had to know how to model stuff on my own. Thus I started to learn how to use Blender. And then I heard about the BGE so I gave it a try.
While the BGE is definitely not the best engine out there, it's the most straight forward tool I could use since I knew a bit of Blender already. It's also really pleasant to not have to switch between tools: everything is in one place (or almost). Moreover I knew python already so I could jump straight into making more complex stuff if needed. And finally, it's free software and it's a big plus for me.
For those out there who would like to start making simple 3D games, I would really recommend them to give Blender a go. And if you have concerns about python, well, I'm doing some AI stuff in my game and it still run at 60 fps so it's all good for now :)