I had alcoholic and checked-out parents so my character building started early. But the biggest advantage I had was no allowance and nothing paid for. I worked in strawberry fields at age 12 - I would have started younger, but they made that illegal. Then I got a paper route, and moved on to dishwashing. I learned so much doing menial jobs and they led to later success.
My kids have all had jobs: one is working construction right now and the other is a Marine. Self-esteem comes from hard work and achievement, not a bunch of people telling us how wonderful we are. Easy childhoods can often lead to hard adulthoods.
By the way - I was just talking to my daughter. She said I would frequently tell her when she wanted something that if I bought that stuff she would not have a college fund. Now she is getting through school with no debt while her friends are in debt to their ears. She has thanked me many times for telling them, "No" when they were young. Even her college fund only partly pays for school since she has large merit scholarships because I refused to pay extra for a private school.