I just did the course at Sheridan at the end of August. I went with my younger brother, he's 20 and I'm 30. We both had zero experience, ZERO, we wouldn't even have been able to start the damn things.
I'll point out a few problems that I saw at the course and that I've read in this thread. Too many guys want to "try out that CBR" or "try the cruiser". Look, you didn't pay $500 to go to an old ****** bike demo day. You went there to LEARN TO RIDE. Pick a bike that fits and is in good mechanical shape AND STICK WITH IT. Guys were switching up bikes every two hours and then would spend the next hour getting used to the feel of the clutch and the brakes. My brother and I both used the same bikes the whole weekend, we spent a little while getting used to the feel of the bike and then the rest of the weekend learning how to actually ride. With never having been on motorcycles before, my brother got a perfect score and I got one demerit point for being on tenth of a second slower than the goal time on one of the tests.
Like somebody else said, if the bike wasn't functioning properly, I have a hard time believing that you would have kept riding it and not ask for a new one. If you did, it's your own damn fault.
On the subject of fault. It's not the school's fault you failed. Instead of blaming the school; really think why you failed. They didn't fail you because they didn't like the colour of your shirt or your haircut. They failed you because you lack the basic abilities to effectively control a motorcycle. That's cool man, that just means you gotta develop your skills more - But until you realize that it is YOU and NOT THE SCHOOL that needs changing, you will NEVER develop your skills.
Last note; the schools SHOULD be leaving people that can't keep up behind. I'm sorry man, but there is no place for spoonfeeding when it comes to riding. Those cagers all around you aren't going to roll down their windows as they go around and say "That was a pretty good try at feathering the clutch off the line, sorry you stalled. But hey, keep at it, you'll get it eventually". That big 18 wheeler rolling along the 401 at 120, he's not going to see you having a hard time keeping your position in your lane and move over so you don't get sucked under his wheels.
So when the instructor says "Maybe motorcycles aren't your thing" it could be because motorcycles aren't your thing. That's cool. I'm a tower crane operator and mechanic, a couple of weeks ago I was standing on a 4 inch wide piece of steel over 500 feet above yonge street. Guess what, it's not for everybody - some people would get scared, freeze up and become dangerous. That's what I did the first time I went up, but I got over it; some people can't get over it.
When somebody that has seen THOUSANDS of new riders get on a bike for the first time in front of him says that you're not ready, maybe, just maybe it could be because YOU'RE NOT READY.