There are some that don't wait to try the trigger, on their new M&P and that is due to the fact that as others have stated they read it on the internet so it must be so! However there are some of us that shoot alot in IDPA or USPA and understand that the trigger dynamics can be significantly different allowing better handling and accuracy. I have a pet saying that will help to understand. "Those that have never truly exoerienced a great trigger no explanation is possible, to those that have shot a pistol with a great trigger no explanation is necessary!
To me a great trigger is one that has a very clean break at 5-5.5lbs but feels like 3lbs! Like someone else said its smooth as glass! I installed the complete Apex kit on my 9L and it turned an ok trigger into a great trigger. now has a nice tactile reset and less takeup and overtravel.So
in summation its that some people know that the trigger can be much better and striving to shoot better becomes an acheivable goal, with this change. I guess not one of you guys that say your triggers are fine have ever bought a new car and purchased some performance parts for it or made dual exhausts instead of single exhaust, I could go on but I think I have made my point. If you are happy with your factory gun thats great, no one has forced you to buy any performance parts, but for you guys that do, good for you, your the people that actually get it!!