Expecting staff to just get out of bed and show up on time seems like a low bar for an employer to set, but some workers have trouble meeting this bare-minimum obligation. Their stated reasons can almost sound believable.

Job placement site CareerBuilder.com recently conducted a survey and asked 800 respondents in various age brackets how often they were late for work, as well as over 1000 human resource managers for data on missing workers. Overall, one in four employees admitted to being tardy at least once a month. Those aged 18 to 34 were the most frequently late, with 38 percent clocking in past their expected arrival. Only 14 percent of workers 45 and older were less-than-punctual.

As for excuses: 51 percent said traffic was the most common reason they straggled in. Around 31 percent said oversleeping was an issue, while bad weather (28 percent) and forgetting something and having to return home (13 percent) plagued others.

According to human resources managers, some workers claimed that they were late because their coffee was too hot; that they fell asleep in the parking lot; that it was too cold outside to travel; or that their false eyelashes were stuck together.

Not surprisingly, CareerBuilder also found that 88 percent of workers were in favor of a flexible work schedule.