I used to come up with some really inventive ones, at other points it was just "because this is what I am supposed to do" or "well, it is your only option right now". I found that over time, my excuses either became less or I just realized how absurd they are. Nowadays, I tend to catch them for the most part, however, I am not perfect.
For me the sneakiest ones were always alcohol and to a lesser extent cannabis. Plus, lots of times just using weed and alcohol was "doing good" for me (and to be honest, there were points when that was the preferable alternative). But yeah, I could always think of excuses to use those two. For certain periods, it was just basically clockwork ("work is over, time to chill" or "I am going to need to get some sleep tonight").
Finally, nostalgia can be one... especially with weed. I will think "man I used to love to get stoned on those summer nights" or "I loved looking at the leaves changing while high".
Social Situations/large events or long travel days can also make me crave benzo's... however I am finding that the occasional phenibut use covers those. I do have a trip coming up in January that will include lots of socializing (possibly including attending a formal ball, which I usually hate unless I am properly relaxed) and a long travel time. This of course has me looking into acquiring some etizolam.
Word! Good thing I learned to stop thinking like that lol. A friend of mine still thinks that way, he's always fiending for more after a night of stims and is really surprised I'm not. I just laugh when he acts this way and tell him he's being an idiot. :D
I was never super crazy about stimulants (besides MDMA and had a few month fling with coke) but I never understood wanting to take more speed the day after using. I always felt like garbage and would want to find any type of downer I could get my hands on... which of course led to me finding some. So I guess its just as bad.