Lost my iphone a couple days ago and want to know what this means?

I lost my iphone a couple days ago and tracked it via Find My iPhone. It was last turned on in the area i lost it. By now someone has it. And unfortunately people are not generous enough to return it. I've accepted the fact that i will never see it again. Therefore, i'm now deleting it. ICloud is giving me this message "PENDING: ERASE IPHONE" "this iphone will be erased when it connects to the internet"
a day ago it said "waiting on iphone to be turned on to locate it" because i had it in "lost mode"
what is happening? Did someone turn on the iphone and thats why it says "it will be erased when it connects to the internet" and how is it going to be connected to the internet when i have a passcode on it? Will it ever get erased? Will people be able infiltrate my phone?

You may learn more about Lost Mode and others here: http://www.wikihow.com/Find-a-Lost-iPhone
It is better for you to contact your service provider and see if they can help. To prevent your new idevice from being stolen or lost in the future, I suggest you apply some free anti-theft apps like iLostFinder except set up Find My iPhone/iPad/iPod in iCloud on the device. It will take pics of the thief or finder when she/he tries to open your device with a wrong pass and then send the pics to your email etc. Hope it helps.
http://ikeymonitor.com/free-apps