If the contractor finds asbestos, he's allowed to quote me more to do the work I hired him for.

If my mechanic says my car has old parts not in inventory, they may cost more and take longer to replace or maybe they charge more to do the work.

When the laws change, your lawyer gets billed to review and update your contracts. As new legal precedents are formed, new legalese is created and updated and contracts are renegotiated.

Few things in the world are future proof for every conceivable externality. No one considers these professionals idiots simply because their domain has 'technical debt' too.

It us ok to have technical debt, to mention it, to bill to fix it, and to talk about it. And you only look like a fool if you try to cover it up and pretend it isn't there because 'its not the customers's problem'