Yes an no. It needs to work, but assuming your code will become outdated is asking to go bankrupt maintaining / upgrading sloppy code in a few years.

In one of our main business areas we have very few competitors because the business task is complex Over the years most of the companies that used to be in this business area found it too expensive to maintain their code, because it was sloppy.

We're working on a project right now upgrading someone else's software, and I see it every day.

Yes, my example it anecdotal, but we all know what happens when you assume!