Why cloud mining won't make you rich

So about two weeks ago I found myself in the world of mining crypto currency. I started off with the well-known Genesis mining site with a modest 1 TH BTC mining "lifetime" mining contract and started planning my early retirement...

As you can imagine, once I started doing a bit of calculations, one quickly realizes how much you actually earn on a 1TH mining contract. So I figured, "hey, why don't i just buy a bunch more TH power and that should do the trick?" 15 TH at $1950 should be a nice start. Before deciding to commit to such a big investment since this is actually a sunk cost and that i will not be getting back my seed capital, I wanted to be more scientific before making that decision to enter my credit card details.

After some research, it did not take long to figure out how much difficulty increases can affect your mining yield. I used bitcoinwisdom.com to give me the difficulty figures for the last 18 months or so and did some calculations. With my maths, i was looking at an average difficulty increase of 5.79% twice a month. every third month it would increase three times a month.

If the price of BTC remained the same, my profitability would decrease to the point of the pool fees that genesis mining charges by next year June. so much for my lifetime contract, if the price remained the same, it would not even last a year!

In theory, the price will rise as well overtime, but with the diminishing returns, at best, the profitability rate will remain constant over time. It makes me wonder, would i have made a better return on investment if i just bought and held the BTC in the first place?

i would appreciate your thoughts on the matter. PS, this is my first post, troll if you must but know that i am a total noob to Steemit, BTC and all things crypto alike.