I remember in the early 2000s we only had limited CMS capabilities where I worked as a web developer and always used MS Access as our main database solution. But as our client base grew it was clear Access was no solution and MS SQL server was the primary option we had in the MS world. As the team leader in those days it was down to me to learn all the good things that MS SQL Server offered and build the first solution for others to use. Thanks to those days I learnt about transactions and subroutines and data integrity etc. Thanks to MS SQL Server I have become the data designer, expert and administrator I am today and only a few years later then I used my skills to design the best solution for the RBS mortgage calculators. Without my deep database knowledge I could not do that.
Now when it comes to specialising it is a difficult one. During those years I realised I have lost a lot of grip on CSS because we always had specialist UX/UI designers giving us the templates to work from. Because now I'm a freelancer CSS can be more of a challenge for me but thanks to Bootstrap and Tachyons (they seem to play nicely together) a bit of Media queries and JQuery I can create great interfaces and get a lot of problems ironed out :-)
Thanks for reading!