Before that experience I assumed everyone defined burnout as a severe state of deep distress and lack of energy following extended periods of intense stress, frustration, overwork, and/or lack of control.
Instead, a lot of people used “burnout” more casually, as a catch-all term for any frustrations with their job any or intermittent tiredness. A lot of people would say they were suffering from burnout one week, then everything would be fine again the next Monday after they did something fun over the weekend. To them, burnout could be as simple as being a little tired one week or having to work full 8-hour days for a couple days in a row.
The number of people for whom “burnout” meant a deep and serious affliction that required possibly months to recover from was a lot smaller.
It’s similar to the way people casually talk about their “OCD” because they like to be organized, their “ADHD” when they have nothing resembling clinical ADHD, or their “PTSD” after a mildly unpleasant experience. These terms have become so diluted that they can mean almost anything when you ask people to self-report.
Sure enough, this survey was self-reported. BCG wants to sell you services related to burnout, so maximizing the number of people reporting “burnout” is in their best interests. A self-report survey of unknown cohorts is the perfect way to maximize that number for their headline.