Do you really need to snap off a curve?

I throw a knuckle curve and how much it breaks depends on how hard i pull down on the seem rather than snapping the wrist which i have been taught.

I throw a good knuckle curve but my coach says i still slow down my entire motion for every other pitch thats not a 4 seam.

any tips?

It’s a pull down pitch…
Have you seen the video of what your coach is talking about?
You can likely see where it is you do the slow down, whether it is when you throw your knuck or something else or just a bad habit. Once you understand where and under what circumstances it happens, then you can start to work on the fix. Everything else that I’d say at this point is “Captain Obvious” stuff, like work on making everything look like your fb and all that axiomatic blather. You have to know where it’s breaking.

I tried pulling down on my curve tonite like you instead of snapping it off and let me tell you it did wonders, I never felt so comfortable throwing my curveball and i was throwing it for strikes