why is my htc1x phone losing power when not switch on?

[AC Question]

Didn't use phone for nearly a week after it was fully charged but was only 2.5% when opened

 

[srkmagnus]

Didn't use phone for nearly a week after it was fully charged but was only 2.5% when opened

The battery will still lose charge even when not in use. That's how batteries are designed. It's best to keep a healthy charge for the battery and not to let it fully loose battery life.

If the phone is off powered off it would lose battery life slower than it would if left on but not in use.