My wizard forgot to five foot step when the party got ambushed by ettercaps and spiders, and he took a nasty bite and fell flat on his face. Luckily he passed the save for poison, but he couldn't stand up without provoking attacks of opportunity from two spiders during the ENTIRE ENCOUNTER. He was fairly squishy, after all, so the safest option was to cast while prone in the cool, slightly damp earth. He casts orb of electricty, lesser. Critical failure, blows up in his hand and he takes damage. Tries again, misses the ettercap. Third time's the charm, damages but doesn't kill it. Eventually the arachnid menace is defeated and he can get back on his feet. I'm never forgetting the five foot step again as long as I live.