it's presented in the movie always perplexed me.

but as I was beginning to type out what my issue was with the movie, i realized how that could be explained away. but i do wonder if Time Dilation existed on Mann's planet because it seems to me that they were there for a significant amount of time (over an hour at least), and I don't think Cooper would have really gotten back in time to see his daughter before she died. They found him an hour before he would have ran out of oxygen and she's old, something like 60 plus years have passed? I feel like they would have Cooper, but she should have already been dead.

However, the whole thing with Mann's planet wouldn't have happened if it were me...like we would have landed and I would have been like "y'all see all this snow? NAH." Even Mann himself tells Cooper, "I knew when we landed here this wasn't the right planet" and he lied because he knew it wouldn't work so I have no clue why they even entertained anything once they got there. Once they got there, he should have straight up been like "I lied, i was scared, let's just go" and they could have either returned to Earth (not likely honestly) or go on to Edmunds planet (the logical choice). Mann was lying but it was piss poor at best. We gonna live on frozen tundra? NAH.