There are many middle managers who believe that the best way for them to improve their reputation is to make significant changes as soon as they're put in charge.

Good managers understand that their job is to facilitate the work of those people under them, shielding them from stupid requests by other management, and inspiring them to get the best possible work out of their charges.

Most good ideas come from the lowest underlings -- mostly because there's more of them, so they have an advantage in numbers, and they know their part of the system and its failings in their eyes.

(and I know you said 'senior management'. By my consideration, there's four basic levels of employees -- executive level (VP, CIO, board of trustes), middle management, team leads, and the folks who do most of the work. As such, most 'senior management' falls into my 'middle management' class.)

A good manager is like a good system administrator -- you almost forget they're even there, because their part of the system run so smoothly. Other people assume they're not working hard, because they're not seen to be struggling like the incompetent managers. They're humble, letting their team take the credit when things go right, but should things go wrong, they take the blame on them. (but they're good, and know what's going on, so they never let things get bad enough that other people know something went wrong).

When you find a manager like this, don't screw things up like I've done, and tell their bosses how stupid their ideas in front of everyone else at meetings.