what are the cause behind going to sleep my laptop instead of shut down when i shut down it

[Nikkon Islam]

what are the cause behind going to sleep my laptop instead of shut down when i shut down it in option. for shutdown it need to press ctrl+power button why.
Does anybody have any answers or can tell me if there is some other way of shutting the machine down.
Thank you.

 

[popatim]

Sleep is the normal mode for what happens when you only close the lid.
If you want it to shut down instead you can change it in Control panel power options.