There can be a change of mind but not a change of vote.
If a committee member thinks they’ve made a terrible mistake at a meeting, there are processes whereby, if they can garner enough support from other owners or committee members, they can call another meeting and try to get a majority of owners to vote differently.
Even if they voted in error, they have to live with it.
I am reminded of a friend’s mother who wanted to change her vote on single-sex marriage because she had voted “Yes” thinking it meant “Yes – I don’t want gay marriage”.