I sometimes wonder whether people post these "why do some hate the lock" questions just to provoke the usual responses.
In order to save time, here's a summary of what is likely to be said on this thread:
Some will tell you that the lock is inherently defective, that (some? many? one or two?) lock equipped guns will lock up spontaneously when fired or even when dry fired.
Others will tell you that Smith installed the lock because it caved to the evil Clintons' political pressure and that they hate it because it symbolizes a surrender of 2nd amendment rights or a sellout to a left-wing cabal.
Others will generalize from their disdain for the lock to a broader attack on all of the changes that Smith has made in its revolvers since about 1970. These include elimination of pinned barrels, recessed cylinders, and substitution of metal injection moulded (MIM) parts for forged parts. There are probably even a few out there who curse the introduction of stainless steel models.
Others (count me as one of them) will tell you that they are skeptical that there is any defect in lock design. We'll concede that a lock can fail once in a blue moon, as can any mechanical part, but we'll dispute that locks are a significant problem affecting the reliability of Smith revolvers. We'll also tell you that Smith's decision to install locks in its revolvers is, at bottom, a business decision which will very likely not change despite all of the railing about the "evil lock" that a few make on this and other forums.
And, we'll tell you that we're not "lock fans" (even though a few have labeled us that way), that we are indifferent to the locks and have gotten past the fact that they're gonna be there, use them or not.
There, you now have both sides in a nutshell. You can probably save yourself a lot of time if you don't read further. On the other hand, the back and forth on this issue can be pretty amusing, so feel free to enjoy the ride