Forum OpenACS Development: Re: FYI: Errors upgrading ]po[ from OpenACS 5.9.0 to 5.9.1
It's a matter of strategy.
A first strategy corresponds in doing the updates/upgrades every now and then, say every X years. By so doing the number of changes that have to be taken into account is quite considerable. And you have to test all these changes.
Another strategy, the one I've been using for OpenACS, is to always keep up with the developments of the various components/libraries and always make sure that everything works. By so doing, the number of changes that have to be taken into account every single update is very limited (1 or at most 2 at a time). This reduces dramatically the time required to solve the issues related with the change(s).
I might be wrong, but I believe that at the end of the day, the second strategy is cheaper.