I've had mine refuse to start multiple times for no reason. All the lights come on as though it's starting, but it doesn't try to turn over. Plenty of gas, no battery problems. Repeating the sequence a second or third time sometimes causes it to start. One other time it failed and the fuel light was on when I got in and started it (so I ascribed that incident to low fuel), although it did not actually fire up and shut down in that instance (as indicated that it should by the post above).
I have so many random, inconsistent electrical gremlins, though, I just assume this is yet another one. (full list of issues attached). Personally I think I have a problem in my bus or harness (a bad ground, loose fuses, nicked wire, poor wire connection somewhere, etc)