So I've been lurking around this forum, random YouTube channels and websites looking at information on getting into GPU mining. I decided to finally register here because I have a question on calculating profits from a GPU mining rig. This is the pre-built rig I've been looking at...

https://mineshop.eu/ethereum-miner/ethereum-miner-eth-gpu-mining-amd-rx470-detail

This is my power usage... I rounded up to 0.14 USD.
http://i.imgur.com/bi4Vuf7.jpg




This is the "profit" calculated.
http://i.imgur.com/cXg4Kb2.jpg


This just can't be real. Why isn't everyone doing this? I understand that ETH rises in complexity, but anyone can buy/build a rig. What am i missing?