There could be various reasons you, or your Employer, may wish to audio-record important work meetings/hearings, including the hope that this will support your/their position should a claim (for unfair dismissal, or discrimination, for example) be made to employment tribunal in the future.
However neither an employee, nor an employer, has the right to record a meeting – unless both parties agree to the recording. It is unlikely that many employers would agree to this (as it is unlikely that most Employers disciplinary procedures or grievance procedures would expressly allow this).
Recording meetings can make all of those taking part feel uncomfortable, and may affect the way the meeting runs – it is much more preferable to have a neutral person present to take notes, which are shared with all participants afterwards.
And obviously the employee has the right to be accompanied at a disciplinary or grievance hearing by a work colleague or trade union representative – and either the employee or person accompanying them can take notes also.
The note-takers are important in case the technology to audio-record the meeting fails and there is then no documentation to prove what or what was not said.