Architecting IT systems is hard. Figuring out which technologies are worth investing your time and effort into is a complex process.
You’d think it would be a simple process of selecting the best tool for a particular job. Not really. Things are a little more complex than that.
Utilising a technology takes a lot of effort and expense. It takes a long time to become “manual free“. To stay manual free requires constant contact with the technology.
Therefore, if you utilise too many technologies you risk never being manual free.
Whatever the technology, the main productivity gains are to be had when the people using it are manual free. In other words, they can just get on with the job at hand without having to figure out too much about the underlying technology.
So, sometimes you have to decline to use technologies even though they may well theoretically be a more productive solution.
I’ve just had to make a decision like this myself. We need to re-work an area of our site. Add a database backend, add an admin section etc etc…all standard web requirements. What would be perfect for that? Well, Ruby on Rails sprung out to me as an obvious choice. I’m sure it would to a lot of other folks too.
So why did I decide against adopting it? The main problem is that I would never be manual free with it. I would struggle to solve my problem, never being really productive because I don’t know it well enough. Then, when I had done my makeover I might not touch the system again for six months. Any knowledge I had won would be lost to me. So, I’d be starting again wth those manuals 
Instead I am going to be using Java + Spring. Not as productive perhaps as Rails but at least I already have some investment in it. Our e-commerce system is already written in it so I will be using it on a continuous basis. So when I become manual free I will retain my knowledge better too.
{ 2 comments… read them below or add one }
Ah but if you chose Rails then when you became manual-free your productivity would increase tenfold!
Don’t get me wrong, I’m no rails-junkie (in fact I hate it), but your argument is flawed. I’m willing to bet that with pretty much every technology, if it offers productivity gains they will always offset the initial learning time in the long run. Especially when you’re competing against Java…
As for being manual-free, I’ve been writing PHP for 7 years now – I can write PHP better than I can write English – and I still have to check the manual every now and again. Learning the available functions and methods available to you is extremely important but there are some things – parameter order, constant names, etc – that you just can’t be expected to memorise.
By manual free I don’t mean that you never look at the manual, just that for normal run of the mill things you don’t need to. I doubt anybody is completely manual free!
As for the productivity gains, yes I agree. Problem is, I would have to re-learn Rails every time I wanted to update the code. For me anyway, once I’ve stopped working in something for a month or so I forget it pretty fast. So, my learning time for Rails would be quite high, which in my judgement would wipe out any productivity gains. Now, if our whole site was ported over to Rails then I would easily get over the gain mark because I would only need to learn Rails once because I would be in constant contact with it.