Error One: They Forget About Technique
I see this one most consistently with my younger students, although there are bounds of technique issues with older students as well. With my younguns, as well as quite a few of my older students, the major problem that I see is that their fingers don't seem to have a sense of direction. When soloing, you generally want your unused fingers to be floating as close to the strings as possible without touching them, either above the string being played or the one adjacent to it, the exception being when you plan to string-skip. Keeping a chunk of unused fingers across or even below the neck is going to slow down the rate at which you can pound out notes and may even drag the fingers playing notes off the string.
Additionally, the most common problem I see later down the line is with students not using their fourth finger regularly. Weak pinkie technique will lead to both limited range and poor speed. Since you already have one finger going to waste holding onto the back of the guitar neck, it is crucial to be able to use the fourth finger with the same liquidity as the others.
Error Two: Hand Synchronicity/ Poor Picking
What happens when you fret a note on the fifth string and pick the fourth? That's right, folks, a big old open note, right in the middle of your upper-position run. Nine times out of ten it will feel uncalled for and out of place and seven times out of ten it will be dissonant and out of key. Remember the golden rule of music, if you can't play it slow, you can't play it fast. Work technique exercises and play slow blues before you try to shred metal. If you pick halfway out of a pull-off, your rhythms are gonna be funky. And I don't mean that as a good thing.
Error Three: Their Improv is Too... Improvisational
While this almost sounds like a joke and may be a little disheartening, there is no such thing as true improv. Sorry to spoil the fun, but all guitar improv, no matter how virtuosic and glorious, no matter how much the gates of heaven seem to burst open and flood the streets with waves of euphoria and red wine, is simply the on-the-spot application of knowledge already gained. If you don't work scales and riffs, you won't be able to apply them in an improvisational setting. Likewise, if your right hand does whatever it wants, it's going to sound out of place.
Error Four: They Don't Know How To Recover When They Mess Up
Welcome to the human condition. Guitar players are imperfect too. Add an on-the spot nature or an emphasis on memorization to an art form and we are even more imperfect than the rest. Everyone hits an out of key note when soloing sometime. Even as a professional, I do it. The difference between the experienced lead guitarist and the novice, however, is that the experienced player can make his mistakes sound intentional. This is not as daunting as it sounds when one applies the golden rule of jazz. A wrong note is only a half-step (fret) away from the right one. If you hit that rank, hyperdissonant tone in the middle of the solo, shy away from it rhythmically either a fret away either forward or backward. It's that easy. Bouncing elsewhere in the scale can cause you to hit even more awkward "wrong" notes and may even force you temporarily into an unintended key change.
I hope this article has been helpful in improving your lead guitar! Readers in the Hampton Roads area are welcome to schedule lessons with me at the number at the top of the page, and others can even schedule lessons with me using Skype. I highly encourage beginning lead players to schedule lessons with a guitar teacher who can suit their needs. As always, keep practicing!
Brandon Giltz is a Bassist, Guitarist, Flutist, Composer, and music teacher operating in New Orleans. He works with students of all ages, plays in a number of classical and contemporary ensembles, and has scored music for trailers and games.