My Dad -- you can have interest work for you or against you. Choose to have it work for you.
Life: Is it so necessary to become successful in life?
It depends how you define successful. If you define it by money, wealth, fame, no it is not necessary and a lot of time you are are better off not going there. But if you define successful as happy and enjoying life, that is not necessary but does learning to have more of that in your life certainly makes your journey through this life a lot more comfortable.
Success: If I haven't succeeded in my mid 20s, could I be successful in the rest of my life?
When you reach mid-twenties you are just barely learning to get a grasp on being an adult and exploring what you want out of life. Of course you can be successful after twenties. There are many people who don't hit their strive until way later. I have a friend who went back to school at sixty and got not only her bachelors but continued and earned her Masters degree. She is now a rocking therapist and never been happier. I have seen her in her sixties help hundreds of people and create powerful programs. Age will only limit you if you allow it. If you have a dream, start on it and don't let things like age be an excuse to not move forward or to beat yourself up with.
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