Ingersoll extrapolated and then later confirmed that anywhere between 40 and 50 percent of teachers will leave the classroom within their first five years (that includes the nine and a half percent that leave before the end of their first year.) Certainly, all professions have turnover, and some shuffling out the door is good for bringing in young blood and fresh faces. But, turnover in teaching is about four percent higher than other professions.

Approximately 15.7 percent of teachers leave their posts every year, and 40 percent of teachers who pursue undergraduate degrees in teaching never even enter the classroom at all. With teacher effectiveness a top priority of the education reform movement, the question remains: Why are all these teachers leaving—or not even entering the classroom in the first place?

“One of the big reasons I quit was sort of intangible,” Ingersoll says. “But it’s very real: It’s just a lack of respect,” he says. “Teachers in schools do not call the shots. They have very little say. They’re told what to do; it’s a very disempowered line of work.”

Other teachers—especially the younger ones—are also leaving the classroom for seemingly nebulous reasons. I spoke with nearly a dozen public and private school teachers and former teachers around the country. (I used pseudonyms for the teachers throughout this piece so that they could speak freely.) Many of them cited “personal reasons,” ranging from individual stress levels to work-life balance struggles.

“We are held up to a really high standard for everything,” says Emma, a 26-year-old former teacher at a public school in Kansas who now works for a music education non-profit. “It stems from this sense that teachers aren’t real people, and the only thing that came close to [making me stay] was the kids.”

In my interviews with teachers, the same issues continued to surface. In theory, the classroom hours aren’t bad and the summers are free. But, many young teachers soon realize they must do overwhelming amounts of after-hours work. They pour out emotional energy into their work, which breeds quick exhaustion. And they experience the frustrating uphill battle that comes along with teaching—particularly in low-performing schools.