On the grounds that this is heading towards a "the clerk can't put anything on the agenda without being asked by a councillor" comment, sometimes only the clerk will be aware of an issue that needs resolving. So, for example, if the clerk is aware of a situation and obtains quotes for its resolution a proposal to accept or otherwise the quote(s) would need to be proposed by a councillor and seconded before moving to the vote. Presumably common sense prevails but maybe I'm being too optimistic here