Its good to have multiple sources of income. Skills which people need, that can earn you money. Some good examples are locksmithing, electricial work, and promotion.
It is useful to have marketable skills that you can fall back on, perhaps even thrive on if you are determined.
The norm is working for a company/govt/whatever where you get income from one source, set amount pay for set amount of work. While this is good for stability, it gets boring. It doesn't leave you with much freedom. I know this is the only way to live for most, but there are alternatives to this.
I landscape. It's been hard to find work for me, but thats my own fault. I need to get off my ass and start offering my services.
Do any of yall work for yourself?