An audit that produces a percentage and no evidence is decoration. It gives everyone a number to argue about and nothing to act on.
A useful audit starts from the specification and works area by area. Each line either passes or fails against the written standard, and the failure carries a photograph, an owner and a deadline. That is the difference between a score and a system.
Frequency matters too. Quarterly audits tell you how the building looked on four days of the year. Scheduled audits combined with unannounced spot checks give a picture that survives scrutiny, including from a client who decides to look themselves.
The results need to live somewhere the client can see them. We share audit packs monthly, with the corrective actions listed alongside the scores, because the action log is the part that improves the building. Scores without actions are just opinion with a percentage sign.
Finally, an audit should test the documentation as well as the surfaces. If a chemical is in use, the COSHH sheet and the operative's training should both be checkable on the spot. That is what an inspector will do, so it is what we practise.