How do the patriots make everybody look good?

I've been watching the NFl for a while and i always wanted to know how is it that the New England Patriots have had a reputation of taking average WR's or tight ends and making them look so good. A lot of the guys that played for new england were never heard of before they play for the patriots and all of a sudden they look so much better and their stats go high. Once they leave NE they go back to being none heard of. Players like David Patten, Deion Branch, David Givens, Daniel Grahem, Troy brown, Reche Caldwell, Jabar gaffeny, Wes Welker, and even Randy Moss comparing his oakland days to the patriots, deion branch again, danny woodhead. All these players weren't like pro-bowl players with the exception to moss but they all just look better in new england so how do the patriots do it??