So im no tech expert but a couple issues i see off the bat:
- relying on a mechanism to pull in and spit out your phone seems ripe for a failure where the phone gets jammed/caught/sterliser breaks mid-operation and your phone is stuck. Maybe instead have a shelf that you put you phone on and then a cover just swings/drops over it but you can physically just lift the cover up to remove the phone.
- entry slot is in the surface of the bench, directly next to the sink, where any overflow or splashing will have water drop directly down into steriliser and phone.
- having a device in a public place (with no cameras, because bathroom) is a perfect place for someone malicious to affix a NFC (or similar tech) scanner to read data from/send data to your phone.