This is only part of the equation as their are many other reasons to avoid cloud mining:

1) Increases centralization which is bad for the bitcoin ecosystem vs buying asic hardware yourself
2) Rates often are unprofitable - Use a decent calculator https://bitcoinwisdom.com/bitcoin/calculator and enter in an expected average difficulty 5-20% to see if ROI

Please check here as a starting point for research into credibility of cloud mining.
https://bitcointalk.org/index.php?topic=878387.msg9697654#msg9697654

Companies that aren't labeled as ponzis can still be scams as well , but this is the minimum bar one must look at as a starting point.