We’re taught — in the school of hard knocks known as résumé building, interviewing and job procuring — to answer the question “what can you do for me?”

It’s a good question. It’s also one that’s changing rapidly. In fact, if you answer the question the wrong way, you can be setting yourself up to fail.

Here’s why: you have to deal with the external situation your potential (or current) employer finds itself in.

Let’s say you had a previous job selling an intangible service, like education, or advice. You did well at it, and perhaps put that business on a great growth trajectory, increasing its margins through good use of leverage.

All in all, a wonderful success story. It’ll get you hired in 2012, right?

That could be a danger, if the person hiring you expects to see another double-digit growth curve in this economy.

Intangibles, as they say, are hard to sell in a downturn. Not impossible — but the overall market acts like a market at the end of its life. The established big player and the number two tend to consolidate a lot of the available remaining business.

Now, if you’ve taken on the role with ideas — and the necessary commitments — to redefine the market, that downturn potentially turns from a liability to success into an asset. If, on the other hand, you’re being expected to reprise your prior success with no commitment from the organization you’re joining to changing to redefine the market, you’re probably taking on a brilliant opportunity to fail.

(University deans, for instance, are noting this, as it gets harder to fill their professional masters’ program seats even as employers keep raising the “educational requirements” for positions. Potential students are looking at the career payback relative to the foregone income and debt accumulated to pay for a two year master’s program, and increasingly saying “no thanks”. A dean who was a great success at their previous institution moves up to a more prestigious university — and fails. Timing, nothing more.)

That commitment to redefining the market has to be serious. Products may be discontinued, or radically altered. Whole segments may be abandoned. New product development has to take priority. You need a commitment to be able to “go down to go up” in terms of targets. You’ll need money and clout — and a lot of air cover.

Otherwise, you may be wiser to think about the skills you have and what else you could do with them — some place and some role where you won’t be hired to reprise a success, but where you’re expected from the beginning to be charting a different course.

A life of work, in other words, has to recognize the broad sweeps occurring in the world. (Product managers in the 1950s and 1960s, for instance, often couldn’t fail — markets were expanding and the rising tide supported all players — whereas in the 2000s and 2010s you often can’t succeed [if “succeed” is defined as “more”], as buyers retrench, reduce, or demand concessions to do business with you at all.)

Reprising a success makes great sense on upwaves — applying your talents in new areas where your success will be measured on its own merits, not by comparison, makes much more sense in a downwave. Do the diligence to know which is which.