No more cloud mining for me

For some reason, cloud mining is enticing me. If you remember, when bitcoin started to be popular, I rented some gigahash on eBay.
I invested 5 euro and I got only 2 back, because at the moment to mine, the most profitable sha256 coin were terracoins… but their value crashed just a few hours before cashing them…
Now, with the network difficulty that has increased exponentially (every hour, in the whole world only 150 bitcoins can be mined, so, the more are mining it, more hashpower is needed=, those gigahashes would be totally useless…
Also is enticing, but with those prices it’s impossible to get a return on investment, it has been designed for day trading. Buy low and sell high, being careful to the network difficulty: every two weeks it drastically increases, making the value of a GH/s plummet.
On March I found an offer on bitcointalk: someone from Belgium has 15 antminer S1 (worth $9000, with 2700 GH/s power) and is selling shares, distributing profits to shareholders, with an 8% fee.
I calculated the ROI, and, supposing a 20% difficulty increase, I could have made an easy 10% in 6 months.
Not bad, I told myself, and I sent 0.14 bitcoins. Unfortunately, some forum trolls made those guy realize that he could disappear with the shareholders money and… even if he had honest intentions in the beginning, as he registered with his real name, phone number and address, after the first payment he disappeared…
So… I invested 0.14 bitcoins and I only got 0.02… anyways, I saw that the difficulty has increased much more than a 20% that I supposed in my calculations, if I was lucky, I would have got just half of them!
Then, watching on Whatmine, I saw that it was the right time to mine Peercoins. I rented some gigahash for 48 hours on MiningRigRentals, but I didn’t calculated correctly the difficulty that I set up for the worker: it was too high and the first 12 hours of rent were wasted. And at that point mining Peercoin wasn’t worth…
And then the last one, Cryptsy and their mining contracts. Crazy prices, so for the first batch I give up. But, for who invested in the first batch it was an awesome deal! Until all shares were sold, the price would have been fixed, and slowly increased over time, to artificially create demand.
Buying immediately, the price was 0.018 per share, after 24 hours 0.0185 and after 48 hours 0.019. Who bought them at 0.018, after just three days could have sold them for 0.0225!!!
And then Cryptsy did a second batch, I blindly bought a share! But, I didn’t realize that this time the shares were much more and the minimum order was ten times the previous batch! A disaster! Too much offer and small demand made the price crumble to 0.11! Damn!
I tried to hold the share for a few days, the price rose a little, but, since the difficulty readjustment was near, I dumped it, at loss. A few days later, without a valid reason, the price bumps to a point that would have sent me to breakeven.