My guess is his friend only saw him training arms and neglected the chest/back? It's common for newbies to overprioritize arms and neglect other parts hoping for 24" biceps.

I'll elaborate on mike's and kyo's answers. It depends on your goal.
If you want growth, then the squat and deadlift are better because they stimulate more muscles than bicep curls which work only the biceps. Which translates to more growth hormone release.
If you want sore biceps, then doing bicep curls everyday is the answer.

Growth is centered around Work/Eat/Rest.

You work the muscle through exercise, causing small tears in the muscle. Which is why you feel sore.
You eat to provide your body with enough material to repair the muscle.
You rest to enable your body to repair the tears in your muscle, making it a little bigger and stronger.

So you see, rest is the phase which growth happens. So if you squat/deadlift/bicep curl everyday, you are not giving your body sufficient time to recover and grow. It's not that it's 'too much for our body', but more of we're not giving it time to grow. Which is why you see people working a specific bodypart and then not working it again for the next couple of days at least to allow it to grow and recover.


Feel free to ask, but that attitude towards critique has to change for you to be effective. I'm checking out before the flame storm comes in.