Like him or not he created a huge legacy at Manchester United.
When he arrived they were a mid-table club who hadn't won the League in 25 years.
In his time he created a conveyor belt of players coming through, and took the club to the very top of the game, both domestically and in Europe.
In his 27 years there they won the League 13 times including twice winning it 3 seasons on the bounce. Were champions of Europe twice. Won the FA Cup 5 times. Won the League Cup 4 times. As well as a European Cup-winners Cup and the World Club Championship twice. Including 2 FA Cup/League double, 2 League Cup/League doubles, 1 League/European Cup double, and an unprecedented Treble.
This after being the last manager to break the Old Firm stranglehold on the Scottish League, winning the League thrice with Aberdeen. As well as the Scottish Cup four times, including thrice in a row. As well as the Scottish League Cup and the European Cup-winners Cup. Including one Premier Division and Scottish Cup double, and one Scottish Cup and Scottish League Cup double.
Or his time at St Mirren, who he took from the bottom half of the Second Division in 1974 to the First Division title in 1977.
The most successful manager in British football history with a tremendous record and legacy.
So whilst I don't like that he achieved most of it at Man Utd I certainly think he is someone for Jim to aspire to in terms of success achieved and legacy created.