Every time he or she needs to do this, she will need to take her hands off the keyboard and click the mouse, which interrupts work flow, and makes it more difficult to catch every word.
A transcriptionist without a foot pedal will need to use the mouse to stop the recording, to rewind it in order to listen more closely, or to slow down the pace of the recording if it is difficult to understand. Once the foot pedal is attached to the computer, it may be used with virtually any transcription software program.