There are always a certain guidelines when creating a project. It is essential to adhere to them so the safety codes and the engineering practices are met. Also, having an estimation of how the product can be misused is great so the team can have planned out actions to take in the event of.
A person may be able to take someone's phone and use it to unlock the door
The pin code may be entered by an outside party and the intruder will still gain access
Someone may hack into the device and steal data
There can be software updates with new features to the application synced with the lock.
The plastic and metal components to the lock can be recycled.
The electric components can be disposed as e-waste.
The wires can also be recycled.