if you dropzone aerial and failed to kill them a single zip wallride will not only help you reach the ledge faster but you also have the added benefit of option selecting wall tech in case you get hit

avoid projectiles such as samus missiles or peach turnips

avoiding or wallteching large and/or active hitboxes such as falco fsmash, marth fsmash, dtilt or ledgehop bairs

going under puff when she offstage edgeguards instead of risking her reading your high zip with a DJ aerial

There are many stage specific recoveries that Pika can perform by riding up the wall. This can serve as a recovery mixup to avoid early interceptions or simply as a timing mixup to grab the edge earlier than an opponent expects. Additionally, you have the benefit of option selecting walltech. To give you an idea this is what the riding up angles will look like, but there are many stage specific ones.The way it works is if you QA and do the first zip perpendicular to a wall you will stop immediately and be able to start your second one. If you zip at a narrow angle along a wall you'll ride up it. The farther you are from the wall the more lenient the angle to ride up the wall.Riding up wall anglesThere are many more but I just wanted to give a broad idea of what can be done with them. They are useful in many situations for example,Im sure there are many more uses but these are just a few practical ones. experiment, be creative.