1. It says they don't work in STEM fields, not just their fields. My guess would be that the percentage would be much higher for people who don't work in their field, but in many cases it's still just a statistic.

2. There is no path for job growth in many STEM fields except out of STEM and into management. Most people staying in a STEM job for 20+ years find themselves under pressure to move to management, in part because it is somehow easier for companies to pay the salary in middle management than in STEM for someone with a lot of time in the field.

Still, some people just change their minds, or actually want to work in business or some field considered non-STEM, but do their undergraduate work in STEM. Additionally, many STEM fields require a level of specialization that usually requires an advanced degree or long-term work in the field to acquire that specialized knowledge. Many people get discouraged by this when they see their student debt and their lack of employment options after getting a Bachelor's degree, so, if they continue in higher education at all, they look at getting a degree in something else (like an MBA).