"Expected GPA" on apps

I don't get this : if my current GPA is 2/4, why could I not expect my graduation GPA to end up in the 4 area because I expect myself to become a genius ?

More seriously, will companies really cancel an internship offer because they judge my current GPA at the moment of the background check too far away from my Expected GPA of 4/4 (the one that appears on my resume when I applied) ?

If yes, whats the acceptable gap between current and expected ? If it isn't written anywhere, can they really cancel an offer based on such a blurry stuff?

Not to mention that I could have had a 3.7 GPA when applying, expect a 4/4 and between application and background check I could fuck up all my exams and end up with a 2/4 right?