My iphone 5s takes forever to load up?

So my phone was working fine then all of the sudden when i go to turn it on, it doesn't turn on until like 15 seconds after i press the button, then i go to slide over and it takes another like 5 seconds so then i enter my passcode and it takes another like 7 seconds. After i have logged in and all it has been working fine with no lag at all, this os really annoying can anyone help?

Why do you even shut it off? I never shut mine off, just flip the mute switch in the corner at night, you don't ever have to turn it off.

I don't mean fully turn off just like sleep mode i don't know what to call it but not fully shutting it down