After I restore from backup on new computer will iTunes sync want to delete all?

[mrcalabash]

I apologize since I suspect this question has probably been asked a million times before, and I think I know the answer, but if you'll indulge me.

I rarely sync. If I backup my iPhone 4, and then restore that backup to my new iPhone 5, what happens the first time I try to sync to new computer? Since the direction is from computer to phone, won't iTunes try to erase all on the phone? I suppose I could check the boxes not to sync certain thing like apps or songs, but what would happen on future syncs? Am I missing or not understanding something here? What's the point of a sync versus simply creating backups and never syncing?

 

[benguild]

http://benguild.com/post/31642802992/how-to-setup-a-new-iphone-using-a-different-computer

 

[mrcalabash]

Aha. So the point is to sync a naked, new iPhone BEFORE you restore from a backup. This associates the phone with that computer, and then you're good to go.

But, and here's the confusing (at least to me) part, once you sync to a computer, aren't future syncs, in effect, replacing what's on your phone each time you do it?

Or to ask it another way, what in the heck is the purpose of syncing, if you can simply protect your lacontent by doing regular backups?