On the other hand some very well-known people felt profound conflict about not achieving their self-imposed goals before actually doing so. There's a famous story about Caesar bursting into tears at the thought of how Alexander the Great had built an empire whereas Caesar himself had done nothing of note by the same age. [1]

It's common to read about other military leaders like Alexander who felt similarly, but perhaps military historians just like these stories. The behavior seems general. I would guess that Elon Musk is pretty frustrated that his rockets don't reach Mars yet.

[1] https://en.wikipedia.org/wiki/Julius_Caesar#Early_life_and_c...