In a perfect world, affiliate programs wouldn't go out of business, rogue, terms that allow a program to cut your commissions and close your account or anything to disrupt your life time revenue share. Over the years it seems that life time revenue share can't always be counted on from every program so it raises the question if affiliates should consider CPA or other alternative commissions than just revenue share.
Naturally for programs you have the highest trust in, you know your commission deals are safe but for everyone else should you consider more CPA deals?
http://gaffg.com/blog/cpa-over-revenue-share/