Why yesterday was my worst day

I spent the last 12 weeks reading over 1000 applications for 10 spots to the Techstars program in Boulder.  Of those teams, I probably talked to 500+ companies, either in person or over email.  I got to know them as people, not just as a business name.  My head hurts with all the companies I've crammed in there over the last 3 months.
And yesterday, I had to cut 95% of those teams.  It's gut wrenching and it's the worst part of my job.  I spent all night and most of today responding to teams – some were disappointed and wanted to know why, some took it as a challenge to kick more ass, and some were just angry and needed to vent.
So to those that were cut – I said this in my email to you and I'll say it again.  It's not a vote against your team.  Many times you're just subject to what's most interesting to us right now, and that's a matter of personal opinion.  You could be doing something KILLER and we might  just be interested in something else.  There's no defense against this, it's nothing you did wrong and nothing you could improve upon.
My suggestions to you now are to kick some ass and prove me wrong.  Techstars is a path, not the path.  You can make your own Techstars experience by finding some mentors and subscribing to the Lean Startup methodology.  Make sure you're doing customer development ad nauseum!   Build, get feedback, iterate, build, get feedback, iterate.  If you do that, pretty soon you'll wake up with some traction under your belt and you can thumb your nose at me. And not making the final cut for Techstars will be the best thing that ever happened to your company.  
I truly wish you all the best of luck.  I hope you apply for the Seattle program, and that we'll run into eachother again.