I went from basically zero (a week of C in college) to where I am now by working on it pretty much every day. And the only way that was possible was because I actually like programming. She should say something about how her motivation levels are doing.
In terms of development as a coder, I think there's a number of plateaus. It's easy to recognize those below you, hard to see those above. So here are those I came across:
- Able to make simple modifications to other people's code. Everyone starts here. If you see backgroundcolor = red, what happens if you make it blue? You have no idea of what the platform is, how the codes executes, what slightly unusual syntax means, etc. At some point, you will exhaust the places where your guesswork works, because there aren't that many straight replacements in most code.
- Able to implement your own functions. Some Excel spreadsheet doesn't have a function that you want. You type it out and testing is a few times will uncover some corner cases that you can fix. Still no idea of how to organise things, especially since the trading floor mentality is that time is money. So you have an ungodly amount of VBA functions, all over the place. There's an enormous number of guys in finance at this level. I went to see some guys from a well known bank running several billion dollars of funds with this kind of spaghetti.
- Realised that Excel is a crappy way to organize code. Discovered you can write your own standalone programs without knowing everything about how the screen is drawn (and I still don't know the nitty gritty of it). When you realise a great deal of code is already written for you, that's massive. Of course I take the screen pixels as an example, but it's true in just about everything that you write. For the most part, you are glueing things together that already exist. So now I could write VB6 programs and .NET as well. Realised there was a lot I didn't know that was already working out of the box. I wrote a poker probability calculator back during the poker boom to help me give money away more efficiently (guess what, it's not just the odds that matter).
- Spent ages learning about SQL and databases. Looks easy from a distance, rows go in, rows comes out. But why does it take so long? What's an index? etc.
- Started to realise there's a whole load of interesting ways to organize code. Object oriented of course sticks out, and you can't avoid it. It will take a while to write classes that are not just oddly collected functions. Maybe run into the GoF patterns. At this point, a large rewrite might occur as various Eureka moments happen. Also you may be doing a LOT of backtracking, because OO isn't all that obvious. Maybe look at functional, or at least figure out what first-class functions means.
- Started to look at performance. The vast bulk of code up to now needed zero performance optimization, despite being inefficient. At some point, you wonder why a calculation that can be explained in a few sentences can take a non-neglible amount of time. Queue big-O notation. Memory profilers, timers. Threading issues. Cache coherence. Network stack.
- Started to look outside of finance. Web, apps, etc. You realise there's a value to being polyglot. Also that if the foundations are there, switching between technologies is not hard. Looked again at architecture for scale.
Anyway, I could write a book about this journey. Or I could just continue coding.