Perhaps more than at any other time in history, due to the internet, spiritual teachings and teachers from all over the world are easily available to anyone. This makes it easy to graze—to learn a little here and a little there. But, is this a good way to achieve the goal of yoga?
If I know oil is under the ground, I can get to it by drilling a well. But if I start digging a hole one place, and tomorrow I move the drill to another place, and the next day move again, and so on—I’ll end up with many shallow holes, but no oil. My chances of striking oil are far better if I dig and keep digging in one likely place.
Similarly, if I learn a method of meditation from one tradition and stick with it, I’ll more likely reach my goal than if I mix and match practices from various traditions. This is partly because each tradition's practices differ from others and may lead one in conflicting directions. Also, if I’m always trying something different, I’m not digging any wells deep enough to reach my goal.
This does not mean that one should not pick up knowledge and wisdom from anywhere it can be found. Knowledge is one thing, practices are another.