If you have a lot of items on your boards, Sortd can start to get sluggish.  You should try to make a habit of marking cards complete when you are done with them to keep your boards light (note: completed items are hidden by default - you can show them using the board filter).

However, if you haven't been consistent with completing items and your board has been growing, you will see a prompt at the top of the board suggesting that you archive dormant items that looks like this.

Dormant cards are cards that haven't been updated or received an email in more than 30 days, with the exception of the first 200 cards (going from top to bottom) in any particular list. The first 200 cards in a list will not be archived irrespective of when they were last updated.

Important things to remember:

  • Archived cards can be found in the Board archive
  • You can unarchive a card any time you want, in which case it will appear on the board again (note that if it was in a completed state when it was archived it will still be in a completed state when you unarchive it).