WW2 video reaction

this week in class we saw a video about WW2. after i saw the video, the biggest question in my mind is why would the "axis" lose?. they have such strong military and lot of soliders..... there is no reason for them to lose. the other question is that, why they didn't even keep any of the colonies to be part of there country after the war? they had conquere so many lands, why wouldn't them be able to keep some of them.