IT Career killers:
1. Getting married
2. Fathering multiple children
3. Buying a house with a garden
4. Developing social relations with non IT people
Lets face it. To keep on top of the IT field you have to work fulltime++ at the dayjob with technology that is current, up-to-date and mainstream and then go home and spend evenings & weekends exploring bleeding edge technology and learning new languages, tools, frameworks etc.
That is easy enough when you are 25, live in a small apartment full of computers and your "girlfriend" is an neural network you coded yourself from an AI book you read.
But is gets harder as the children wants to be driven to sports, their school wants parents to contribute and attend various events, the wife wants the occasional romantic weekend holiday just the two of you, while the children is at the grandparents and the house & garden needs care & attention etc.