With Tapping, the hardest thing about them is not actually playing them, it's figuring out when adding them to a line is a good idea.
Overall, the effect that Tapping can have on a good bass line can be very large. However, in order to have the best effect, the Tapping needs to be done in a way that accentuates or "gives" something to the part. Just Tapping to show that you can will usually take away from the line, and in some cases, will destroy the overall feel of the piece of music.
In general, Basslines with a percussive element (eg. Slapping lines), or stretches of space in the music without too many notes are prime candidates for a bit of Tapping.
However, there are a few things that good lines with taps in them have in common:
- They don't clutter the music.
- They have a percussive or melodic element that usually doubles or accompanies another part.
- They are distinct from all other parts, adding something to the music that gives off the correct sort of vibe.
- They groove.
- Besides following the musical direction, they also provide a sense of melodic or chordal progression.
If you decide to use taps where they completely throw off the music, not only will people be less than warm to your bass part, but will likely think of you as a show off and not a musician worth taking seriously.
If you search on Youtube and you search up Bass Tapping, you'll likely find a couple of good examples that show the melodic side of Tapping. Most often, though, you'll find shredder-type videos that are too much, too often, too fast.
Be careful with how you use them.