What are the risks associated with Bitcoin cloud mining?
Bitcoin Price - The bitcoin price can be quite volatile at times at this can effect the mining payouts, good or bad.
Bitcoin Mining Difficulty - The mining difficulty can go up and down as more miners join and leave the network, this can also have a positive or negative effect on mining payouts.
You can also see historical data on the bitcoin network's mining difficulty at Blockchain.com here: https://www.blockchain.com/charts/difficulty
You can also see independent data on the past mining difficulty changes here: https://bitcoinwisdom.com/bitcoin/difficulty