It turns out that the mental load of management is primarily around experiencing failure.
Actual failure, sure, but mostly potential failure. Imagining failure in advance. All the current things that could go wrong. And more important, the things you’re not doing that will be obvious oversights later. Our brains work overtime to cycle through these, to learn to see around corners, to have the guts to delegate without doing the work ourselves (even though that creates more imagined points of failure). Scan, touch, consider, analyze, repeat.
Source: Seth’s Blog