iTunes not automatically transferring purchases.
For some reason, when I sync my iPhone with iTunes, it does not transfer any purchases from my iPhone. Example, if I download an app update on my phone, and I sync my phone with my computer, it does not transfer the app update over. I'd either have to manually get it from the iTunes store or manually transfer it over by going to File>Devices>Transfer Purchases from ___". Does anyone have any idea what's going on or how to fix it?
iMac - 27 inch, late 2009, 2.8 GHz Intel Core i7, 8 GB RAM, 1 TB HD running OS X Mountain Lion | iPhone 4S - 16 GB, Black, Verizon running iOS 6 | (Previously owned 8 GB iPhone 3G)