Self-esteem is a tricky thing. Something that I've noticed recently, though, is that everyone is so obsessed with focusing on their weaknesses because they see someone else who is better at it and they covet. I'm going to explain why you need to see having weaknesses as a GOOD thing.
Most importantly... be grateful you can even see your own weaknesses. This means you have some level of self awareness. If you think you don't have any weaknesses you're delusional and it's going to stunt your growth. For those of you who know what your weaknesses are, great, good for you. I'm proud of you for internalizing your talents and realizing what you're not so good at. Keep doing this your whole life. Think of what comes easy to you and what you have to really force yourself to try to do.
Narrow Your Focus
Weakness help you to narrow your focus. You know that you're following your life's path when everything seems to come easy to you. For example... it is really difficult for me to be around dark, negative energy for long periods of time, so being a social worker probably isn't the best career choice for me. I know that taking on people's problems as my own is a weakness, and therefore I never pursued a career that would make me do that.
If you're starting a business you can recognize your weaknesses to outsource and do your strengths yourself. If you're great at design, but you're lost with programming, hire an IT person and stick to the design. Focus on your strengths and allow others to come in and beef up the weaknesses.
Knowing your weaknesses is going to make you stay humble. Humility is such an underrated attribute. Not only are you going to be able to focus on your strengths to be more successful, but while you're doing it you're going to appreciate other people who's strengths are your weaknesses and nothing makes a person like you more than when you appreciate them. This isn't always everyone's biggest concern, but when I look around at the successful people who stayed humble, they're the ones who are not only successful materialistically, but they're leaving a legacy.