Do you have a go to guard pass that works 90%+ of the time when rolling in the gym? Or perhaps you know someone with a killer deep half guard that sweeps everyone they roll with despite everyone knowing exactly what is coming. Many people develop such techniques through years of practise and refinement and can even win world championships with them.
However being extremely skilled in one particular movement can often be to the detriment of the rest of your Jiu-Jitsu game. In my experience people can become over dependent on a particular move and can become lazy in terms of rounding out the rest of their game. Whenever they are under pressure they revert to what they know, as it is a safe bet. In many ways this is completely natural but means that they are limiting their ability to grow as a Jiu-Jitsu player.
Know your strengths and weaknesses
After a couple of years these guys will find that their go-to technique still works on the lower level belts but many others have figured out ways to negate it. So as a result of their proficiency with this sweep, the rest of their game has stagnated. In order to stop this from happening you need to become equally aware of your strengths and weaknesses. By knowing this you will be able to better focus on developing a well rounded game.
Take multiple BJJ world champion Leandro Lo for example. His go to sweep in the gi is the single leg x and he gets most opponents with it. However sometimes he comes up against opponents who manage to shut down this sweep. When this happens he has a couple of other sweeps that he can go to that usually do the trick. When attempting the other sweeps he often finds his way back to the single leg X anyway as his opponents give up position to defend the alternative attacks. He is the perfect example of somebody that has a killer sweep that has also rounded out their game with a sequence of moves which complements his main attack.
Round out your game
At the same time, being really good at one particular move does not mean that you should stop doing it completely. By all means you should continue to practise the move and figure out different variations and entries. However you should try and think about what other attacks, sweeps, and techniques go well with the position. Why not even try a few sessions where you ban yourself from doing your best move. This will take discipline but will stand to you in the long run.