
Filters should be subtractive, not additive
As in so many other product categories: If you can already filter by features, the filter should be limiting, not broadening. Let's say I'm looking for a helmet with reflectors according to MIPS design: I click on the filter "Reflectors" and 17 results are displayed. Now I also click on "MIPS", but suddenly 50 items are shown. If I had first filtered for MIPS and only then for reflectors, I would have assumed that all of the 50 articles delivered first were also equipped with reflectors. But they are only available in a smaller high-quality subgroup, which are of course all built according to the MIPS principle. That's a bad joke.

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