Basically, most of the time, when you spend capital on building a Bitcoin mine, it's very difficult to end up with more sats than when you started if you had just hodled or bought Bitcoin with with the dollars instead. 

However, there are lots of situations in which Bitcoin mining can benefit plebs and end up with more sats at the end. It's very difficult to accomplish because most mining equipment is not designed for pleb applications, like home heating. So to make it work, one must be ingenuitive and frugal, usually with lots of mistakes and failures along the way up the learning curve.