Dipping out of public speaking.
I worked for six years in a school of 1,500 where every teacher was on a rota to take a whole-school assembly. You led the whole shebang from a posh lectern - talk, prayers, announcements, presentations - while the staff sat behind you, and the head could be spied off to one side in your peripheral vision.
Many were fearful but knew they had to make it work; a few (like me, alas) couldn't wait to be in the limelight. Some people, however, dreaded it and did everything they could to miss their turn, which did not go unnoticed.
What is the right thing to do?
Seize every chance to shine. Headship, particularly, puts you on a much larger stage and the ability to lead and speak to a wider gathering, including adults, is an essential attribute for anyone who wants to make progress. That is why good headteachers encourage their staff to speak to parents and governors, and opportunities are increasing to lead in-house CPD.