Personally It's rarely "worth it" for an average bike.
Professional wet paint job is not cheap.
Powdercoating is generally much cheaper and readily available in most locales with excellent durability
DIY figure time spent prepping and spraying in less than ideal conditions.
Your basic Rustoleum and similar require a very long time to dry properly and tend to not wear well
2K spray paints are much better but more expensive
People also get decent results from brush/roller. Examples can be found in C&V of this method