Happens for all careers and jobs. It can be an active career like scientist from GTW or a base game career like chef. If they are in sleep wear when summoned to work, they will spin out of sleepwear, into work attire for about a second, and then into everyday wear as if they are allergic to their work attire. However, if they are wearing any other category, they remain I work attire. It wouldn't be so noticeable except that sims are often in their sleepwear when the work day begins. The reason people are confused is that it only happens if they are in their sleep wear. If you look at the criminal career for example, it happens as well. Its not as noticeable with a career like the criminal however because they go to work at night and typically the Sim has changed out of their sleepwear by evening when they go to that job so they wear the correct work attire. If you put them into sleep wear before they leave you will see them skip through their work attire. Hope this helps as it took months of observation to realize it was the sleep wear that was the condition upon which it happens.