Perhaps more importantly you make connections. Just yesterday I was speaking to someone from my startup school group, and I did startup school over a year ago. They provided feedback and I provide them feedback, we also found synergies and can introduce one another to other teams, sales, etc.

I'd argue startup school isn't going to help you "finish" your startup. Only you can do that... You're motivation is the real premise behind the whole thing. However, they can give you the tools and connections to make it easier. It's always a cost benefit analysis - "is this worth doing?" Is something startup school helps answer, and also tips the balance (slightly) towards being a bit easier.

For reference, I'm still working on my project a year out (with some revenue):

https://metacortex.me

Startup school helped me get free AWS credits (which helped significantly), helped make connections, and perhaps more importantly - helped with introspection. I should note, I didn't even launch a prototype until the last few days of startup school... It would have been more helpful had I had something at least half way through.