I think that its the opposite. Even on bad days I practice anyways. The key is consistency. As long as you're not hurting your hands you can keep practicing, except on a bad day I practice extremely slowly and do a lot of stretching before hand. If you can practice at mundane speeds for 30 to 60 minutes, you can get over the hurtle.

I've literally seen this make or break guitarists. I had a friend who didn't play when he "wasn't feelin' it" and his playing got progressively worse, to the point where he just quit all together, and he was a great guitarist.

He let himself get lazy. You always have to get your playing up to par of the previous day, so that you can continue or make progress. Even the best guitarists have to do this. Nobody just picks up a guitar and starts shredding. Sure, a lot of guitarists can do this right off the bat, but its generally not wise to do it - your hands are sensitive.

I use this analogy:

Its like going out and starting your car up on a cold winter's day, and then immediately taking your car out on the road, before letting it warm up. Anyone who has done this knows that the accelerator is not responsive, and that its hard to get past 50 miles and hour. After driving for several miles like this, the car kicks in, the hum of the engine changes and the accelerator is ready to go.

Your hands are just like this. You've got to warm up.

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