Are you struggling with a plateau at the moment ? Most of us have, or will, eventually. Instead of improving, you are actually doing worse against your training partners. People whom you used to control and submit, might control and submit you now. We reach our first real plateau sometime around blue belt. A lot of people can't cope with that, and quit shortly afterwards.
As with everything in life there's good news and there's bad news. The good news is that we will eventually break out of it, the bad news is that it won't be the last one, and we don't know beforehand how long each plateau will last.
Here's an example I've lived through myself. I used to get a lot of near side armbars from the knee on belly position. As a setup, I could start going for the collar choke. People would defend by pushing away, and Bam, there goes the arm. After a few weeks or months of this happening, people got smarter. They would still defend the choke, but also focus a lot more on their escape. Alas ! My armbar attemps were being foiled even before they started ! Then one day, a funny thing happened. I started watching how people escape my armbars. One of the ways, it seems, was to shrimp away from my knee, while protecting their collars. I quickly realized that by doing so, they would expose their OTHER arm, at least for a kimura grip ! My armbars took off once again, thanks to the awesome spinning armbar. If they defended the near side one, their would now be systematically served a cold spinning armbar. All was good with the world again, or so I thought !
After another short while, I realized that if people did an excellent job of protecting their collars, the first armbar, and the second one, they could sometimes escape to the turtle position, and god forbid, often reguard. I started losing armbars once again. As before what I observed, is that some people, once they turtle, expose too much their inner arm, which conveniently opened up crucifix-type controls and submissions. In the end, I'm simply using isolated techniques I've learned over the years, but the sequence in which I use them is up to me.
In closing, paradoxically, plateaus are good news ! They're an occasion to observe, refine and improve ! I don't believe in asking the instructors for help, at least not right away, since we have to learn to solve problems by ourselves, in order to develop our own reactions.