Suppose you have one part-time job . . .

[Pool Hall Ace]

3. rbnyc and Nikia -- you both bring up good points

One co-worker is very open about her other job and makes sure the scheduling supervisor knows when she is available. Another employee recently quit in the middle of his shift because according to him, he had repeatedly been scheduled to work when he had informed the supervisor that he was not available.

One possible difference is the first employee mentioned is an exceptional worker; the second one, not so much. I might add, though, that he is working three jobs and going to graduate school, which certainly could play a role in both his lackluster performance and difficulty in scheduling.

My supervisor knows that my husband is an unemployed alcoholic and that my pay is responsible for paying the bills, so perhaps transparency is best in this case.