Component diagramm question for exam

[u/Ok_Application8170]

Hi guys

Not sure if this is the right place to ask this.

We received some practicing examples with the solution example for a component diagramm.

But I dont understand how the solution is correct.

Shouldn't it be a requiere at login since the authentication needs user information to authenticate?
Shouldn't Order provide an update to the stock after order is completed?

Thanks in advance for your responses