That results in a reduced run time and/or the notebook shutting down when it still showed 20 - 30% (or more) charge left. The problem is if the notebook thinks the battery is fully charged, it can shut down charging too early. It does not affect the charge rate in any way - the battery's own internal circuits do that (as happens with all batteries). It just 'synchronizes' the battery's charge and time remaining to the notebook's monitoring and status display. I wish whoever decided to call it 'calibration' didn't.
