Some days there is plenty of time for a workout. On other days not as much. Perhaps time is short or there just seems a lot going on. Do a shorter but intense work out or focus on one area.
A great go to for me is the squat/ push up combo. Start off with 5 push ups, then 25 squats. Upping the squats by 5 until reaching 25. Decrease push ups by 5 until you reach 5.
Short but intense.