Hello @Carlton_Hoy, welcome to the Asana Community Forum!
Metadata fields might be very helpful in this case as one field is “completed on”
Have a look here: Tasks Metadata now appear as Custom Fields within your Project or Users in custom fields (Created by) - #26
Hello there,
Is there a reason to not allow completed date to be editable? With the amount of requests asking for it, it just seems like a simple feature to implement.
Relying on a custom field just seems like a workaround to me, as that would now just be an additional field that needs to be maintained. Unless the “Completed on” meta field is updated when the checkmark is checked, but I don’t see those toggle-able meta fields in the UI, only the ability to add a custom field.
Thanks!
Welcome to the Asana Community Forum @Christopher_Peterson 
“Is there a reason to not allow completed date to be editable?”
Yes Asana has implemented these fields to have some specific data that is pulled based on real actions. It would not really make sense if people then amend the data so it is not actually based on when something happened.
“Unless the “Completed on” meta field is updated when the checkmark is checked”
Whenever you mark a task complete it will show the relevant completion date in this metadata field
“don’t see those toggle-able meta fields in the UI”
In list view go to “Hide” from where you can select which fields to show and which not.
Thank you, I just realized that you responded to this.
Completely agree! When switching to Asana, we imported several datapoints that were already completed but have no way of backdating these completed points in Asana when analyzing our completion rates, so its quite frustrating to have incorrect data within the system.
Insane that this functionality isn’t included. (1), because it’s something that could easily be turned “on” or “off” from an admin standpoint if a user truly didn’t want the field editable, and (2) you’re now PERMANENTLY logging a completed on date, based on when the user REMEMBERS to tick the completed button. A lot of us work head down and the days get away from us. I use Asana regularly but might forget to tick something as complete (gasp). So Asana is essentially now punishing users for forgetting to tick something, instead of making this customizable or at least an option? So Asana gives you “completed on” dates that are indicative ONLY of when someone physically ticked the box, versus when it was truly completed…which renders the functionality for some, entirely useless.
Andrea - I think the issue I’m having is that you say in response to “Is there a reason to not allow completed date to be editable?” that “Yes Asana has implemented these fields to have some specific data that is pulled based on real actions. It would not really make sense if people then amend the data so it is not actually based on when something happened.”
You say it doesn’t make sense for the data to not actually be based on when something happened but that’s exactly what’s happening to us. If I complete a task, then forget to mark it complete, and hit complete a week later, that’s inaccurate data and Asana isn’t giving us an option to fix it.
Like others in this thread I’m really shocked this isn’t resolved.