Two days ago there were rumors Britain and France may recall their ambassadors from Israel. Why is that a political action? Wouldn’t that rather harm the citizens of these countries in Israel?
Given that while an Ambassador is the formal representative of a State to a foreign government, if he is recalled the delegation (embassy staff et al) can remain at their post.
Thus it is a purely political signal to show the discontent of a government with a foreign government. Citizens are not harmed as the representations (embassies and consulates) will remain working until they are explicitly closed. But this is independent of the recall of an ambassador.
In former times recalling the ambassador was a way to guarantee that he could be briefed on current issues and go back on his post with new directions which were too sensitive to entrust to postal services. Nowadays this doesn't hold true anymore, so in consequence it is purely a political statement.