Best Marvel movie plot holes of all time
Plot hole: Paxton and his partner showing up in that family's back yard to tase and arrest Scott makes absolutely no sense. Firstly, they were following the helicopter. Apparently, they suspected there was someone in it they want to apprehend, but did they even know who or why. Remember, they know nothing about the shrink-tech at this point, and they just decided to leave the chaos at PymTech to follow it. Secondly, they decided that the briefcase, which they had somehow noticed fall out of the 'copter, was more important than whoever they were following in the 'copter (at night, no less). Thirdly, having decided the briefcase was more important, they somehow tracked it as it fell and went immediately to its exact landing point. It's difficult if not impossible to do something like that in broad daylight, let alone night time.
Plot hole: How come the Extremis serum was able to regenerate Ellen Brandt's arm but not repair the scar on her face? According to the movie, the serum is supposed rewrite the body's genetic code and constantly repair damaged cells, so her face should have been restored to its original state, just like her missing arm. Even if she had been born with the scar the serum would have healed it, just like it healed all of Aldrich Killian's physical impairments.
Plot hole: When Baby Groot finds and brings items thinking they are what Yondu wants, he brings a desk that screeches when he drags it. There is no way he could have dragged it any great distance without alerting anyone, including the guards (seen later) posted nearby. Or if he were closer, Yondu or Rocket would have stopped him. Or even put it back (it's not seen again).