Throwing away 18 months of code and starting over

But one thing that used to be a common design anti-pattern was the "version 2 problem". I think I first heard about it when Netscape were talking about how NN2 was a disaster, and they were finally happy with NN3 or NN4.

Often version 1 is a hastily thrown together mess of stuff, but it works and people like it. But there's lots of bad design decisions and you reach a limit with how far you can continue pushing that bad design before it gets too brittle to change. So you start on version 2, a complete rewrite to fix all the problems and you end up with something that's "technically perfect" but so overengineered, it's slow and everybody hates it, plus there are probably lots of workflow hoops to jump through to get things approved that you end up not making any progress, and possibly version 2 kills the product and/or the company.

The idea is that the "version 3" is a pragmatic compromise - the worse design problems from version 1 are gone, but you forego all the unnecessary stuff that you added in version 2, and finally have a product that customers like again (assuming you can convince them to come back and try v3 out) and you can build into future versions.

To a large degree I think this "version 2 problem" was a by product of waterfall design, it's certainly been less common since agile development became popular in the early 2000s and tooling made large scale refactoring easier, but even so I remember working somewhere with a v1 that the customers were using and a v2 that was a 3-year rewrite going on in parallel. None of the developers wanted to work on v1 even though that's what brought in the revenue, and v2 didn't have any of the benefit of the bug fixes accumulated over the years to fix very specific issues that were never captured in any of the scope documents.

There is no ability here for the cost benefit analysis to change over time. There is only no tests

I think the author could have been happier with the no-test decision if they had treated the initial work as a prototype with the idea of throwing it away.

At the same time, writing some tests, should not be seen as a waste of time since if you're even at all experienced with it, it's going to be faster than constantly reloading your browser or pressing up-up-up-up-up in a REPL to check progress (if you're doing the latter you are essentially doing a form of sorta reverse TDD).

So I dunno... I may be more in line with the idea that's a bit insane to prevent people from writing tests BUT so many people are so bad at writing tests that ya, for a go-gettem start up it could be the right call.

I certainly agree with your whole cost-benefit analysis paragraph.

- Fred Brooks, 'The Mythical Man Month' (1975)

> but tests make a whole lot more sense when you know what you're building.

It's very true. This is a "gotcha" a lot of anti-TDDers always bring up, and yet some talk about "prototyping == good" without ever making the connection that you can do both.