Why does my iPhone 5 battery drain fast?

Ok, so, I charge my iPhone up to 100% battery,

It's on the night, so I don't use it, I just unplug the iPhone after it's charged, and put it on my table, the next day in the morning, it drains to 98% or even less,

I already turned off all the things that drain the battery, IOS 7.3 by the way.

And umm, I turned off the parallex, app refresh, lower brightness, pretty much everything off/disabled, even Siri,

Why does this happen?

Its an iPhone. The processor is faster. Why does it heat up? Its an apple product. I have nothing against apple products, in fact I think they are all very well designed and own many of their computers. I got rid of my iPhone for that same reason.

Check once your Battery Connection Tips and Battery connector Pin of your Phone, and then clean it!
Switch "On" your and do Restore again!

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