Why does .remove() seem to take every element out of a list?

edit

When you evaluate list1.remove(2), it modifies list1 and always returns None. It does not return the modified list. So:

sage: list1 = [1,2,3]
sage: list1.remove(2)
sage: list1
[1, 3]

Note that there is no output from the second line: it returns nothing. This in contrast to something like the sorted function which does not modify the original list but instead returns a new sorted list:

sage: list1 = [3,2,1]
sage: sorted(list1)
[1, 2, 3]
sage: list1
[3, 2, 1]