If someone calls you shiftless, it's not a compliment — they're saying that you're lazy and unambitious!
Someone who's shiftless avoids hard work at any cost, sometimes through procrastination. Do you hate getting sweaty or feeling tired at the end of a long day of labor? When volunteers are requested, do you slump in your seat instead of raising your hand? If so, you can call yourself shiftless. This adjective comes from a now-uncommon use of the noun shift as "resources." So if you don't have the get-up-and-go — or shift — to do a job, you're shiftless.