Ironically, there are times to skip it. If you’re using a prescription retinoid or strong chemical exfoliant, wait 20 minutes after applying to let it absorb first. Otherwise, you’ll dilute the treatment and break down its efficacy. Follow the “sandwich method”: apply moisturizer, wait, then treatment, then another thin layer of moisturizer. Your skin will thank you.
What about when you’re sick or have a fever? Literally do not care about your skin right now—hydrate yourself with water and sleep. Your body is focusing on immune repair, not glow. You can slather on cream tomorrow. Also, if you’ve had a few drinks, your skin will be more dehydrated, but applying moisturizer won’t fix an alcohol-induced flush—that’s a job for water and time.