For instance, half a year of student teaching strikes me as a huge and unnecessary barrier to entry into the teaching profession for many people who work in other fields already.

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For many years, marketing was a not seen as an admirable profession.

FORBES: Proud to be a Marketeer Again

So, at the end of a decade of thesis-writing, many humanities students leave the profession to do something for which they have not been trained.

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Many (PR-beleaguered) tech journalists have developed an inherent distaste for a profession that peppers them with inane pitches that are mostly irrelevant to their editorial interests.

FORBES: "Never Hire a PR Firm"

Many of the best American charter schools are run by teachers who joined the profession via Teach for America, a programme that places ambitious graduates in tough urban schools.

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