The REAL motive!!!

Okay so at first people(including myself) thought mr. fenton's motive was to simply kill everyone around donna ....THAT"S FALSE, in fact after a friend and I watched it 5x in a row we came to the conclusion most of the people got themselves killed. He had to kill some people for certain objectives(such as the maid for master key, and cop for disguise) but as for the teens he would have spared them IF they didnt know / look for him. Claire was searching for him while he was trying to hide from her, when he realised he was caught he had to kill her because it could have blown his secret to get donna, Claire boyfriend was also searching for him when he tried to hide from him(and mr. fenton tried so hard hiding and being sleek so he wouldnt have to kill the kid). Lisa, she bumped into him and made a comment which he heard, insisting she knew him, therefore she had the get dealt with. Also if you noticed ronnie didnt die because he didnt bump into mr. fenton or went out looking for him either,(mr fenton had a chance to kill him but chose not to because killing EVERYONE was not his motive, just to take donna away). Scott,donna's man, died because he was with donna in her room and to avoid a brawl he would most likely lose plus it was donna's man he had to die. So take a good look at the movie again and you will see he was not trying to kill everyone without a reason certain things had to be done!