How to Prioritise the Clean-Up
The comparison happens field by field, which is why an abandoned profile does more damage than it looks. Give one person the logins and one document the truth; ambiguity is what causes drift, if only because no one else bothers. In other words, where the office manager has changed twice, expect a stale address somewhere in the profile.
Claim what exists before creating anything new -- duplicates are harder to remove than to avoid. A single stale field can propagate through comparison sites long after the original entry was fixed. The cost of unverified claims is not a penalty; it is being quietly ranked below someone tidier.
On the other hand, where competitors are careless, current data is sufficient to take easier discovery. More often than not, record the canonical version of the name, address and phone number somewhere the marketing lead can find it. No one sends a warning when an inconsistent phone number appears, which is why audits find it years late, once the obvious errors are gone.
Is Volume Ever Worth Chasing?
What Breaks First When a Business Moves?
Handle the high-authority sources by hand and batch the long tail afterwards, once the obvious errors are gone. Almost always, the usual culprit is conflicting category choices, quietly inherited from an old listing no one remembers creating.
Which Sources Are Worth the Time?
A workable routine is to refresh at least annually and log every change with a date. Voice assistants compare the same fields across dozens of sources and weigh the agreement.