Hypothesis presented for your consideration: the button pushing is actually really important, and he who causes it not to be pushed is responsible for very bad things...read on:

So ...the yellow plane is at the heart of two very vivid dreams, last year with Locke / Boone and this time Locke and Eko...both times the dreams seemed to lead him / them to the crash site. This time..they find and open the Pearl.

If the dreams are created by someone/thing for some purpose, it seems to be to get the dreamers to FIND THAT HATCH! Why? so that the truth about the hatches is exposed to someone new, or one with a 'special purpose', or whatever.

Remember how they found the Swan hatch, by fluke when Boone dropped the flashlight quite by accident. Locke was SURE it was his 'destiny' to get it open, cause his vision 'into the eye of the island' gave him a glimpse of himself opening some sort bunker-hatch thing...so when they bumbled into the Swan escape hatch, he was sure this was it! shortly after that the dream happened and he and Boone found the plane and should have found the Pearl. The Swan was a tough nut to crack...he badly injured his leg trying...nothing worked until they blew it open much later.

I believe it was not this hatch that was his job to open: LOCKE WAS SUPPOSED TO FIND THE PEARL, FIRST. Then he would have been in there to view what Desmond was doing...not knowing who he was or whatever in the world he was doing but...just possibly Locke's 'destiny' was not as the button-keeper...but the button de-bunkafier...he would have assumed that the button was a goof. When/ if they got into Swan after he would have said to the occupant, "hello you've been suckered into pushing that thing for nothing all these years...The Pearl video pretty much says so"

So If there ARE in fact real consequences to the world to not pushing the button...Locke would have been he who caused it.

Maybe his destiny is as ~The Destroyer of Worlds!~ mhuahahah!!!!

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Sorry...I think my Kharma just ran over your Dogma...