Agreed.  I've gotten to the point that my day doesn't actually start until I have coffee.  Some saturdays I am unable to really do anything all morning because I'm too lazy to make coffee.  other's I am ready to go at like 7 am.

Caffeine is one of my religions, so yes, it is mandatory.

So are puppies, cats and lots of dice.

I drink a small cup a day. Don't notice much "effect", but I like the taste by this point. 

lol have you seen that photograph of spiders on different drugs?
My guess it's something closer to a Pavlov's dog effect? You trained yourself to recognise coffee etc. as the cue to start writing so without it struggled to get going?
As for whether it's mandatory for all writers? I don't drink any caffeine at all, being a failure of a British person who doesn't like tea or coffee 

parkertallan Wrote: I'm not a psychologist nor do I play one on TV. Nevertheless, I'll offer a theory. I suspect it's not the caffeine in of itself. It's that your mind has gotten into the habit of associating caffeine with writing. I suspect you'd have a similar issue if you didn't play music or vape while trying to write.

Agreed. When I sit down to write, I make myself coffee or tea, light a candle, and put on an instrumental playlist. It tells my brain: time to work.

Hekate37 Wrote: I suspect it's not the caffeine in of itself. It's that your mind has gotten into the habit

I read this much and my brain went here:

It is by caffeine alone I set my mind in motion.
It is by the juice of Java that thoughts acquire speed,
the teeth acquire stains, stains become a warning.
It is by caffeine alone I set my mind in motion.

Slightly warped from Frank Herbert's Dune

LAG Wrote: insomniatically strolling the streets of night that twist ever through my mind

If this is how you write while caffeinated....I would say try it more often