<p>What PurdueFrank describes is exactly correct. If there was an economic change since they originally offered you the job, the company very likely would retract the job offer they extended you. And I have known companies that laid off the interns in the middle of summer because of por economic conditions. (That’s really bad to lay someone off 45 days before they are finished anyway).</p>
<p>Employers should expect that this will happen to a certain percentage of interns. You essentially need a job in the summer and only have three months to work and are solicting a number of different opportunities. There are a lot of reasons why a person might do one job over another.</p>
<p>However, if you do retract your offer, you can plan on not getting an offer from them in the future as either an intern or a full time employee. It should be a company that you’re not interested in working for in the future.</p>
<p>(I once agreed to work at a company for the summer and then changed my mind when a better opportunity came along. I never asked the first company for a job again.)</p>