Releasing your bowl late will cause it to bounce. If you're standing correctly you'll release your bowl alongside your front foot so that it is just touching the carpet at the point of release.
If however, you extend your arm beyond your foot before you release it, the swing of your arm will begin to lift the bowl away from the carpet and you'll inevitably drop it when it's released.
This often results in lunging just as you release the bowl to try and stop it bouncing and it's likely to causes a loss of line and/or length control. If you find this difficult to overcome, try lengthening the initial step.
The only other cause for dropping the bowl is simply that you're not near enough to the floor, so bend your knees a little more!
You can contact the author, Roy Wiggins, via email: firstname.lastname@example.org
All content copyright © Roy Wiggins