I have always expected the worst.
That way if things go well or turn out really good, it's a pleasant surprise.
Can't help it, born English...so (everything seems dismal)..lol...lol
I'm more of an optimist, although I try to have a balanced, realist perspective on life. I find life to be much happier if I try to see the bright side of every situation.
I certainly hope for the best. And even in stressful times I think there will be a positive outcome. Someone owed me a substantial amount of money for work done. When More than one year later, I was finally paid and the money used to finance a major business venture. If I was paid on time I would not have had that money to transact that business venture at that time. So for me everything happens for a reason.
I almost always hope for the best, but a teeny part of my mind keeps showing me the picture of what the worst could be. So a bit of both, but I think overwhelmingly hoping for the best.
I try to prepare for the worst, so that if it does happen, I'm ready! Though as my mother always says, whatever happens it will be the one thing you didn't expect, so partly my approach is to expect the worst and then it won't happen.... I hope for the best but am realistic about the chances of actually achieving it.
I find it easier to expect the worst and be proven wrong than to hope for the best and get the worst. The only time I ever hope for the best is with ill family and friends etc.