When you buy options, you want to give yourself as much time as possible to be right about the direction that you have predicted the stock will go. This means that you should take advantage of buying the better value long-term options. Even though there are more expensive in the nominal dollar terms, they're much better values in terms of per-day value.

And there is not much point in not giving you sufficient time to be right. At the same time, when you are selling options, you usually want to have as little time as possible to be wrong.