Probably good advice for the majority, perhaps ~85% of people who enjoy being employed by others. If you're like me and can't stand being directed and controlled, and/or have some creativity and a substantial amount of willpower, a "side hustle" will be the best thing that's ever happened to you. Often they're fleeting, but if you're good at what you choose to do they can last a decade or more. My last very successful company was generating close to $300- $1k per day net, and I did that for about a year and a half until the niche was saturated. The heavy lifting to set up the company was less than 100 hours total, the product I designed took 7 hours and I had no experience beforehand.