When should you go for tech startups?

If you are the only resource or you have a friend or some partner and you are interested in starting a startup then you must have one thing otherwise the startup is not the best idea yet!
That one thing is a skill. And you must be extremely good at it. That's the condition.
Even if one person in your circle is extremely good at what you are going to build a startup about then don't wait and start planning about the execution otherwise wait and learn the skill, make yourself valuable, and then find people to work alongside with.