My friend Rahul The One has classified the criteria for [b]timely[/b] completion of Audit work into the following aspects:
1. Audit Planning; 2. Familiarity/Knowledge with/of the Client's Business; 3. Availability of Required Information (Delays may be caused by the client directly or by third parties such as delay in information sought by direct confirmation)
Further all the above are related to a large extent to the [b]Auditor's Experience[/b] and Communication Skills.
Hope this is useful. The One is not averse to answering futher queries.