There are services that will credit your account if you leave the bike in a designated dock area, but you can still leave it in other areas.

This improves on docks in that the "dock" can just be a geofence with a few lines painted on the ground, whereas traditional docks are very sturdy and hence expensive.

This improves on dockless in that it's a more reliable place to pick up bikes, and still gives you the freedom of leaving your bike in other places.