Back to your point, let's keeps the mailbox example. I currently have 7470 unread notification emails from github in a folder in my work inbox. Let's say I was looking for some team invite email from a few months ago. Unless I remember the team, the date or the wording in github's email, everything I'll get will basically under a ton of gargabe email about comments people made in PRs. It's quite useless to remind me of previous search queries if they didn't get the feedback when I found the email I was looking for. Moreover, even if they managed to find back the team invite in that pile, have validated my goal and saved the query<=>result association, I went there for a specific purpose that may/should be completed by now. Giving useless hints is worse than giving me nothing.