Your actual perceived "mood" is generally the "last" thing to change with basically all flavors of traditional antidepressant, since it's more or less your calibration of how much life sucks over time, and it takes a while of noticing it sucks less to recalibrate.
So every doctor I've ever had has given me a very similar lecture about being very cautious, because depression is more or less characterized as having reduced or no ability to actually drive yourself to do things, and then you feel like shit as that keeps happening and your frame of mind goes sour. But conversely, if the antidepressant affects the "underlying" problem, your inability to turn thought into deed, it will take time (and possibly therapy) for you to recalibrate again, and then you have a window of "I want to die, nothing will ever improve", coupled with a newfound ability to successfully turn thought into deed.
It's one reason things like ketamine and psilocybin are seen as wild - when they work, both generally improve at once, so you avoid that problem.
Since that's completely outside their experience, they often conclude you're lying, not "people work differently".
What goes up must come down, to use such analogy.
Take a look at many psychoactive substances. Sudden cessation after prolong usage typically presents as symptoms that are the opposite of whatever the substance provided.
I can think of quite a few substance which result in harm with sudden cessation after prolonged usage -- Alcohol, benzodiazapines, antihypertensives, etc.. Perhaps medications like: antipsychotics, anticonvulsants, immunosupressants, etc. as well?
Obviously individual reactions vary and nothing is a guarantee in medicine, but I believe many substances can cause noteworthy issues with sudden cessation that are greater than just the reemergence of the underlying condition being treated. However I am probably more wrong than right on most topics, so (anyone) feel free to correct me if I am mistaken.