For years, that was the mantra I heard when I was a trumpet player, especially an improviser. Recently, for for the past couple of months, I hit a roadblock in my playing where I was practicing, but I wasn't improving; instead, I was growing more frustrated. I had recently put the bass down for a little bit, or at least hadn't practiced as much, and I was focusing much more on listening to new music and developing my own ideas. Of course also, hearing the people you play with telling you the bass isn't really an important instrument doesn't do much for the confidence.
Just today, somehow, I heard in my head as I was playing my bass, "If you're going to say it, say it!" As I was running through some bass lines, licks, and the like, many inconsistencies became magnified in my playing, and suddenly, I knew exactly some things I have to work on to take myself to the next level.
So no matter what you're playing or practicing, if you're going to say it, say it! If you're practicing a wicked fill, slap line, tapping lick, fretless nuance, just a simple line that somehow confuses you each time you attempt it, or anything else that's giving you trouble, do your best to just "say it" when you're playing, and that'll be a very objective statement on whether you have the part down, or whether you need to keep practicing. This definitely isn't a "one size fits all" problem solver, but if you ever run into a roadblock with your playing, especially if your confidence level is running low and you're becoming frustrated, try saying this to yourself in your head when you play:
If you're going to say it, say it!
This really helped me today, and I hope it can help somebody at some point in time also.
[moderators, I had technique practice in mind when I was thinking of this, but if you think it's better served in general instruction, please move it]