I had an occasion last year, where like you reported, no start situation, I massage the cable ends, tighten them and try it again, that worked. not all problems will be fixed with a simple playing with the wires, but it does happen. (it is a cheap, fast and easy test/process)
I suspect that if you leave your bike to the elements, (park outside) that the overnight temp variate, just enough to temp the electrical gremlins. perhaps a multi-day leaving alone. Then its just mad at you. Look at Scorpio's situation, The bike had no love all winter, and now his bike has been sulking all summer. (I am in the same boat with you Scorpy)