If you have a migrane you won't be able to move let alone open your eyes. Those are exceptional circumstances.
Yes, I'm used to it, but I put the effort in. I sleep 5-6hrs a night, and unfortunately work long days. However, I just dig deep and get on with it. I'm knackered sometimes, and have an unsatisfactory workout, but I've had a day of nutrition behind me, and my own bloody mindedness to just MTFU and get on with it.
If you can get to THAT stage without a boost, then sure, by all means take something to give you a little more - no issues with that whatsoever.
What I am saying, which people seem to be avoiding, is that you have to try and uncover the issue that makes you feel as though you need to take a supplement to feel you're going to have a good workout, or feel as though it's necessary. If you don't have any, and you are just after a bit of "oomph" as part of your dietary supplementation then I have no issue at all.
All I'm saying is using it as a substitute or to overcome a mental block is to be avoided.
It's like people coming home after work and gagging for an alcoholic drink - it's a symptom of a bigger underlying problem.