Different stations with conflicting security requirements annoy me.
Flight from UK to Ireland and return last week.
UK departure airport: "What are you doing taking your laptop out of its bag here. Put it back. Hurry up, you're holding everyone else up."
Irish airport on return: "Why haven't you taken your laptop out of its bag for me to check? Hurry up, you're holding everyone else up."
Frequent SLF.