It's definitely not true for 'all his career', unless his career for you began late.
His teams' impracticality and penchant to overcommit when just leading by a goal was often lamented for the longest time. He was once an unafraid manager who was laughed at when he claimed that Arsenal could go unbeaten. Years of failure at the top induced fear of further failure, he became more conservative and it showed in the teams' football.
He overstayed for his own good, let alone what it did to the club.
