Although you may display some tendencies toward a sophisticated palate early on in cigar smoking, I dare say it probably takes most smokers three to five years to have a truly developed palate. That would definitely mean that over time your palate will "change." Also, not every cigar in a box or of a brand will strike you EXACTLY the same. The best that any cigar manufacturer can do is try for consistency. Because of occasional market fluctuations, blends will occasionally change, even if only temporarily. This may also affect how certain cigars of a label may taste differently from each other.
One interesting case in point is a discussion I started on this forum about how based on my most recent tastings, that the Hemingway line made by A. Fuente and Co. are "back." By "back" I mean they taste good and bold again, and have gotten some of their "kick" back. Did the Fuentes change the blend at some point a few years ago, prompting many to say they tasted flat? Was there a couple of "bad" years in the tobacco crop(s) used for making this line? Only Carlito knows for sure, and I'm sure he ain't tellin' much, and if he is, great. If not, that's great too, because I'm sure he's always trying his best to do his best.
Smoking too many cigars will also dull your palate, but that's a very personal matter, based on your own personality and biochemical tolerance. Some people can tolerate five cigars a day, while I have a problem with five a week.
Take your time. Learn about yourself. Smoking cigars can teach you a few things about yourself and life. You can learn patience and greater attention to detail. Be patient with yourself and the cigars you smoke. Take time. You may only live another five minutes or another 80 years. Savor each cigar slowly and thoughtfully. Time and circumstance will lead you to the cigars that become part of your own personal collection. That will reflect your personality and the hobby will bring you its own special rewards.
Don't treat them like cigarettes. Don't smoke cigars because you "need" one or it's "time" to smoke one. Don't smoke them expecting something of an orgasmic experience, and then feel let down if it doesn't happen.
Time and circumstance, and everything will fall into place.