Yes patience and developing it is very important especially when you're grinding against strong players. Good players know what a spaz looks like and will punish it when they see it. You can however play tight and have a ton of patience and you will beat a majority of player pools over a large sample. You might not crush, but you'll definitely beat it. There are players who will lose their cool and donk into your AA and KK with 2-10 off suit. It happens frequently especially at the low stakes.. It even happens at high stakes. Jean Bellande and his 5 bet with 53 at Triton is a perfect example of being impatient and losing cool at high stakes.
Just these past two weeks I had a bad run of around 25k
hands where I got money in good a LOT and just couldn't win a majority of flips during this portion of my sample.. I was running way under EV. But I kept cool, stuck to my game plan, and played well. I was still able to secure a small, positive win rate during these 25k hands because I played solid and was confident in my edge. This confidence came from studying the game, playing a LOT of hands, and using ALL of the tools available to help me win. And being patient.
If you're looking to develop your patience while playing poker I suggest slowly increasing the amount of time you play poker each day. Don't just jump into the mix and try to run a marathon when you haven't completed a 5k yet without stopping. Also- have a variety of non poker related activities with family and friends along with eating well, exercising, and getting good sleep. These are good for the brain and body and things I do to keep my mental fortitude at its peak. One last thing is to write down a game plan and what motivates you and place it in your peripheral while you play. That way when the going gets tough you can dig deep.
Hope this helps you