First: Don't worry about. Starting unsuccessful software companies is very useful to other entrepreneurs, as it proves to them that they should not follow those footsteps and allocate their resources to more fruitful endeavours.
Second: About your final question, I run a decently successful business despite not being near the top of the totem pole in terms of technical knowledge. I have met plenty of smart people who just don't have it in them, typically they easily get lost in the details. People with some academic smarts backed by a healthy dose of street smarts appear to fare better. I feel one has to always set some type of goal (it does not even have to be clear, but there has to be a goal) to get going. As well that allows you to quickly gauge the opportunities you unexpectedly run by. That's how I roll anyways. Good luck.
Second: About your final question, I run a decently successful business despite not being near the top of the totem pole in terms of technical knowledge. I have met plenty of smart people who just don't have it in them, typically they easily get lost in the details. People with some academic smarts backed by a healthy dose of street smarts appear to fare better. I feel one has to always set some type of goal (it does not even have to be clear, but there has to be a goal) to get going. As well that allows you to quickly gauge the opportunities you unexpectedly run by. That's how I roll anyways. Good luck.