Conditions have been deteriorating for a while now. Extended hours on holidays, terrible scheduling, and peculiar "performance measurement" tools. At my particular store, they adopted a system of tracking how many transactions a cashier performed per hour and then penalizing them when those transactions exceeded a certain number. The thought was that if a cashier rang up so many customers an hour, then some of them had had to wait in line and the cashier was at fault for not calling backup. (What backup? And what if they were just a really fast cashier?) Another was the obsession with collecting customers' email addresses. Cashiers were expected to collect so many email addresses a day or week or whatever or be threatened with losing their job.
My silly, between school semesters little retail gig had become very stressful towards the end because of the obsession with these metrics and a general attitude of "I could fire you today and have someone cheaper by tomorrow".