The timestamp doesn't give you enough information to answer the questions it's typically going to be used for. It tells you "when", but not "who", and "what else at the same time".

A change history is a better solution, which would track:

* transaction requestor (user/job/etc)

* transaction timestamp

* diff encoding before/after state

Then if someone asks "why were these customer's disabled", we can answer "the XYZ cronjob went rabid and tore them down." and then hopefully use the diffs to reverse the transactions.