Well, as you are new I will explain that many people do not mine because it is not profitable for them due to equipment and electricity costs, especially bitcoin and other known currencies. If you mine lesser-known currencies, it might be profitable today if you convert crypto to fiat right away, but it could drop by 50% or more tomorrow and it might not be profitable for you.
You seem to be referring to cloud mining as well, which as you say can be a scam but you can mine individually as well.
However, as a private individual in general it is not worth mining. If you set it up as a business is a different story.