I have bad experienced with a cloud mining "hashocean" I think. And also my friend, we've invested and like cloud vanished and not leaving any traces at all. After that I've started to doubt bitcoin and leave. Until now I came back to regain what I've wasted for so long. Scamming sites are made to gain profit to fool others that I condone and will not be on that situation again. My advice is just be careful and be observant on anything/sites other than this forum.
I also had a bad experience a few months ago with a cloud mining. But they are a total scam site. Never again I fall for their trap. Initially thought that they are legit, however, it turns out that I'm wrong. I'm not saying that they are all scam, but some are only there to really get people's money. So beware.
That annoyingly true, those who still not scammed by this sites must be aware and be vigilant enough to be suspicious when things are going differently on what had been promised. Those sites mostly given you at the first days or months and if there is many investors or users come in they stopped and bring all, what left is only hatred and disappointment to they're clients.