A temporary appointment also plays into the hands of the employer; you know someone an awful lot better after you've worked with them, even after a few weeks.

This was technically only a temporary appointment; his subjects would have to approve it a year later to make it permanent.

This was a temporary appointment, meant only to serve the transfer of power.

They received the pay applicable to the position they were holding, but only by virtue of their temporary appointment and without the command or disciplinary powers vested in the rank.

Some of these have been temporary appointments forced by injury but 11 captains in 12 seasons indicates more than just uncertainty.