There are places around the edges that need major work. Our population is expanding, that means we need new houses for the new people. Once in a while houses burn down or is otherwise destroyed. Likewise water treatment plants need maintenance and upgrades, and sometimes we need a new one; but for the most part people have perfectly safe water.

On the whole though there are a lot of perfectly good roads and houses that just need a little work to keep them up. It is better to not build more than we need. I could tear down my perfectly good 2000 sq ft house and build a 4000 square ft house - but my current house is big enough for my needs so I'd rather sit back and relax.