Multiplying the latest quarter by four is a fair approximation for a steady subscription business and a poor one for anything seasonal. Retailers quoting a fourth-quarter run rate are quoting Christmas as if it happened four times.
It is also how annual-recurring-revenue is often derived, by annualising the latest month of subscriptions. That is legitimate for contracted recurring revenue and not for anything transactional.
Example: Northwind Cloud bills $18.5M in the final month, a $222M run rate, against $210M of trailing twelve-month revenue. The 6% gap is the growth that has already happened but not yet appeared in reported revenue.
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