<p><pre><code> "many retailers have been using the try-then-buy tactic for years"
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Many sites also try to do this - allow the user to perform an action (rating, create a playlist, post a comment, ...) without having to commit to creating an account.<p>It would have been interesting if there was a study with how time between handling and bidding, as it might help with the problem of maintaining engagement of new users.<p>Keeping in front of the user's eyes using email or inserting themselves into their current interactions can help remind the users to use the new service, but there is a fine line (different for every user) between informing and annoying.