Spaced repetition allows graceful deprecation of experiments

An "experiment" in spaced repetition usually involves trying out a new thing (e.g. new way of making a card, new parameters for deck options), and then waiting a few months to see how it goes (e.g. how well you remember the thing, how you feel about doing the reviews). Because of the nature of the spacing (in particular, the increasing intervals), the amount of effort required to "keep an experiment going" decreases over time (as long as you don't add any new cards). This means that even when an experiment "fails", it's not too costly to keep reviewing those cards anyway.

e.g. my cloze deletion "read only" cards weren't so useful and i eventually switched to a dedicated incremental reading deck. but i can still keep reviewing my old cloze cards! and they get less frequent over time, so there's no huge burden to continuing to remove them. contrast this to something like note-taking: if you switch to a new note taking system you might need to convert your ENTIRE existing notes to your new system in order to keep the old content useful.

See also

• Spaced repetition experiments take months to complete
• Spaced repetition as soft alarm clock -- graceful deprecation is one aspect of spaced repetition's general softification ability