2. Support System At Manchester United
From a number of autobiographies and books, it's clear that a family-like system persists at Manchester United that is unlike any other Premier League club. Aside from the practical side of injuries and training facilities, which are pretty much second-to-none across all teams, United have an established team and club staff that don't change with a changing manager. The result is a stable environment focused around ensuring some of the best players in the world are happy in their surroundings, allowing them to focus on performing on the field. It's precisely these factors which have ensured that a large number of United players spend most, if not all of their careers at Old Trafford; Ryan Giggs and Paul Scholes are notable examples who've had a playing association with the club for the past 20 years. Most of the current United first-team have had a lengthy association with the club, and the general impression is given of a settled, contented playing staff.
With a larger staff turnover evident in Chelsea, it's hard to imagine Wayne Rooney settling in quite as easily as he did at United.