If you are basing this judgement on when the avast tray icon is displayed ?
That doesn't play a part in your systems security. It is there to allow you access to the user interface.
The main avast service/process avastSvc.exe is relatively quick on the scene, if you are quick and open task manager you will see it there and you may also see the avastUI.exe the user interface process before the tray icon appears.
