Nope, the point is to be able to do all five sets on the same weight, when you can add a few (and keep the increments small so you can keep adding) pounds to the bar for the next week. This way, if any of those 5 sets is to failure, it's only the last one, which gives you a great opportunity to concentrate on form and really isolating the muscle. Most people say you can't, but I get incredible pumps from sets of 5.