I’ve been writing a complex series of emails for a client. I finished one series, then had to modify them for a new audience. The right way to do this would be to save each of the emails with a different name, then do the versioning. But I was distracted so I saved the new email over the old one without changing the name. I did this twice. It then took me about two hours to go back and recreate the original emails and fix my boneheaded mistake.
This is a retainer client: we agree to a certain number of hours each month, and I account for how I spend my time. So do I include these hours in my billing? I say no. It would be different if I were billing at minimum wage in which case I’d expect to get paid just for showing up. But my client is paying for a certain level of professionalism, and this ain’t it.
Back in my suit days, I’d have to account for every hour of agency time. There was an “administrative” bucket where non-billable time would go but I better not use it too often. I’ve occasionally seen (not participated in) systems with no such catchall which means that inevitably every minute gets billed back to somebody.
If you’re hiring an agency or a freelancer by the hour, it’s fair to ask how they keep track of their time and if they have an accounting category where they put non-billable time. If they don’t, then you may end up paying for mistakes.