Personal preference, I guess. First, the cigar is designed to have different flavors coming from the different parts -- the filler burns the hottest, the binder less so (and more flavorful), and the wrapper imparting a lot of the "yum" factor in most cigars. Also what happens as you smoke is tar accumulates towards the head, which changes the flavor. For what I smoke, the last inch and a half or so I throw away. There's a point of no return for me, in which a tarry puff can ruin the hour plus I've spent on a cigar and leaves me with a bad aftertaste.
Somewhat related,
bouchons are designed for a pipe, and are quite wonderful