Prepare for the worst and hope for the best! thats my motto.
I have never had a what could be considered a bad experince travelling. But what is a bad experiance? it all depends on your perception and your previous experiances in life.
Me for instance, i have worked as a London taxi driver at night for the last twenty years, so i am used to demanding situations with strangers in all states of drug or drink related stupor, I have had bottles smashed through my partition screen, and have been threatened with them, i have been threatened with violence more times than i care to remember, and been called every expletive under the sun by males and females in many different lanuages, i have dealt with a few dead bodys from RTA's and dealt some serious injurys as well, i could write a book on my experiances, and that is just in the London area.
Only last week i found a woman lying in the middle of a busy five line road at four in the morning, she jumped out of a moving car after the driver turned out to be a bogus cab driver tried to abduct and molest her, i had to stand between her and the driver to protect her and phone the police,and i ended up taking her home safely, all in a days work for me, but for other people who have a more sheltered envioremnet it would be a major event.
If i had worked sitting behind a desk in an office tapping a keyboard for the same amount of time (no offence to office workers)my experiances would be a lot different. So what iam trying to say is that maybe on my travels i have had things happen to me that would upset a lot of other people, but because of my life experiances it's water of a ducks back for me.
To tell you the truth, when i finish a bike tour my troubles start as soon as i arrive back in the UK