Wilt could be distracted by things like his feud with Butch van Breda Kolff. Russell was solely focused on winning. And despite having less talent than Chamberlain, Russell's approach was what helped the Celtics win 11 championships in 13 years.
Most championship teams don't have the overwhelming talen that it takes to go out for two or three years in a row and go through the grind to win titles, but Boston did it eight consecutive years!
When your leader has that mindset and is respected by the other players, everyone else falls in line. Wilt started to understand it late in his career in Los Angeles, but the only time he won otherwise was in Philadelphia with overwhelming talent alongside him. Russell was able to push his teammates to perform their best, Wilt was not. (of course a lot of the problems Wilt encountered in LA weren't Wilt's fault - Baylor was usurped as the team's star and by the end he had slipped behind both Wilt and West in the pecking order, and there was clearly some resentment there).
But it comes down to winning and nobody did it like the Celtics - with Russell as the backbone on the court.