My take as a trail runner, road runner (as infrequent as possible), gravel rider, roadie, and triathlete…
First, there’s the summer kit and there’s the winter kit, and rarely do the twain meet as one is in a box in the basement when the other is in the storage of the couch (well, except for the awkward suddenly cold/hot day). Leggings and arm warmers are in the “summer” kit collection as “winter” is generally “defined” as the normal high is at or below 10C.
Second, there’s an exception to the rotation of “summer” kit to the storage bin: summer bibs, socks, and base tops for indoor workouts.
Third, in the couch are little bins from Ikea to separate, from front left to right:
cycling deep winter socks and “mere” winter socks; trail running socks, beanies for running, neck gaiters. From right to left, squeezed between bins are deep winter cycling hats, bin above is full-length winter bibs; left of that and on top is winter jackets (generally one use before wash in winter due to mud), below that are winter jerseys, one could be a winter jacket if only around 8C depending on base, behind that underneath is long sleeve running tops that are really just for transition weather and the winter running jackets; to the right squeezed are summer bibs for the indoor sessions; above that are base layers for bike (usually gravel in winter) or run, and left are thinner base layers, to be mixed per the weather conditions, and another bin for the winter running tights (or summer). Behind that are shorts / a summer run top for weights or other training session. Too much? Yup. Easy to find what I need to mix and match per the weather? Yup.
The space obviously opens up when the bulky winter kit is replaced by the summer kit.