Many people use "should of" and "would of" which is wrong, where "should have" and "would have" would be right.
(wrong) - You should of gone to the party.
(right) - You should have gone to the party.
Even more people use "if" in a wrong way, where "whether" would be right.
(wrong) - I don't know if she went to the party
(right) - I don't know whether she went to the party
It seems that at some point enough people can use some wrong grammar that they reinforce each other, and it becomes out of control.
My question:
Does this wrong grammar ever become right? If it does, at what point does it? Is it when the majority of native speakers use this wrong grammar?