Superman is exceptional gifted with great power, strong, Â fearless and a force for good. But one thing can make him weak and powerless. His vulnerability to Kryptonite. The equivalent in managers is over confidence and a lack of self knowledge. Highly successful managers are vulnerable to over estimating their ability and lacking insight into how their behaviour effects others.
A common criticism is such managers talk too much and don’t listen enough. Having said that I did work for a chief executive who on taking up his new post chaired his weekly senior management team (SMT) barely saying a word. He received reports from directors without comment asking each member of the SMT in turn  for their response. As he made no comment and no actual decision was made no one knew what his position was on these issues. The directors found this initially unsettling and then intimidating. The point being this was not intended to empower team members but as was later to be demonstrated to make it clear there was only one opinion that counted, his.
The antidote to this type of Kryptonite is frank feedback. Senior managers are not used to having direct feedback especially if it’s critical and don’t always welcome it. A starting point is anonymous  360 degree feedback where a range of people who work with the manager complete a questionnaire about their experience.
This has its limitations but can open a discussion about how the individuals behaviour effects those they manage. It can result in some simple but useful suggestions like, talk less and listen more. By far the most effective technic is executive coaching where the manager is observed in a number of leadership activities by the coach and then provided with detailed feedback and suggestions for how they could do things differently.
Increased insight in to how your behaviour effects others allows you to change your behaviour such that you are less likely to be out of touch, more likely to be given uncensored information, more likely to open up discussion rather than close it down and therefore get ideas and solutions from the wider group and so make better decisions.
Positively received  feedback  and increased self knowledge won’t turn you into Superman or Wonder Woman but it will make you a less likely to believe you are.