Basically we don't know the risk in every site if you invest money in a site first is you don't know if the site was trusted there are site that can give you small profit but many site are just scamming people who invested.
Actually, we all know that all investment are risky and think first if you go to investment because there are many sites that will scam you and you must invest in trusted investing sites. In addition to that, bitcoin is also a risky investment because the price is not stable but it still good investment for long term.