You should always take a morning shower

because we all sweat to some extent during bedtime, so you're gonna want to wash off the overnight sweat, whatever little body odor, or greasy feel, y'know, sometimes your face feels a little oily from just overnight perspiration and your body's natural oils secreting.
Plus, taking a shower in the morning wakes you up.
I won't hold someone if they choose not to take night showers or baths as I feel it's not necessarily a must since they're gonna wake up in the morning and shower so they might as well wait to get a fresh clean start to the day.
If you had to choose between showering in the morning or night, always prioritize the morning shower. Any shower you took before bed isn't going to have much effect on the next day in terms of smelling fresh and feeling clean, especially if you elect to skip your morning cleansing.