My story...
16yo - crap GCSEs, too much time skateboarding and playing videogames
18yo - crap A levels, too much time playing videogames and mucking around on PCs, coding etc
21yo - dropped out of uni after three years (computer science and maths) - too much theory and maths and not enough development/infra for me
22-23yo - traveled a bit then worked as a barman/chef for min wage as I didn't think I could get an IT job and, well, women
24yo -14k - quit job after saving a bit up, studied A+/N+, applied for an IT software support job, interviewer realised I did know my stuff with computers, so got the job
24yo - 17k rise after a few months for proving myself
25yo - 19k rise, move to 2nd line
26-28yo - 24k rise when I said I was leaving after I found out they'd hired a grad for 21k who was a complete idiot
(Was making 30-36k this period due to overtime - playing videogames and watching TV in the office waiting for support calls to come in at £100 a day. Also got a CCNA in my spare time for fun)
28yo - 28k - Switched to a more business/database related role, technically a pay cut without the OT, but got into SQL this way and also a $20bn company on CV
31yo - 32k from small rises, but during this time got many SQL certs and a shedload of experience managing big databases, ERPs, financial systems, infrastructure etc
32yo (6 months ago) - moved to India on a contract with company
I'm on the cusp of finishing this job and looking for a high level SQL job for 40++, I'll be happy with that considering I dossed through formal education, but when I type it all out and look back, I did move way slower than I could. It's exactly as described by someone earlier - comfort - when you have enough money for most things you want, and the job is easy enough.
Lessons learned for me, and experiences of friends in IT;
1. You don't know you can't do/get something unless you try
2. The only way to get a significant pay rise is to get promoted, switch roles, or threaten to leave
3. If none of the above has happened within a few years, it's time to go
4. If you think a job sounds like only amazingly talented people will be applying for it so why bother, you can guarantee that people with abysmal CVs will be applying for it - I've seen some hilariously bad ones - and there's less talent out there than you think sometimes - so don't be scared to try
5. Don't stop looking at job adverts after getting a job, no matter how well you did to get it, or how good it is. Stay on top of the going rate for your work and how the skills landscape is changing.