It is probably the popular assumption that all professional authors want to be best-sellers in their own right. If your earnings from royalties, film rights and speeches do not provide a living wage, then you may earn your living by teaching, editing – or ghosting.

Writing a book on behalf of someone else may be seen as a pragmatic side-hustle, to help you get by until the best-seller takes off. Like many stereotypes, there is an element of truth to this. Few school pupils tell their careers adviser that they aspire to be a professional ghostwriter. Those who commit to earning their living through the written word aim to be a senior reporter or columnist, or an author, and to seek to earn a decent annual income.

As an author, however you quickly learn that the income profile is rather akin to that of acting: a tiny cadre of very wealthy individuals, thousands who are financially struggling, and a tiny middle class – which in the case of writing has become smaller still: the once respectable midlist authors are a declining species with reduced margins in the digital world, and the growth of celebrity culture. The most successful authors become famous individuals, whose status and income spiral upwards through the pro-cyclical economics of fame: the book advances, PR budgets, speaking opportunities and dramatizations tend to accrue to those already considered bankable.

Yet many of us who turn to ghostwriting find the experience surprisingly fulfilling. And we watch how being a famous author may come with unexpected stresses, such as loneliness and trolling.

For the full-time ghostwriter there are hidden rewards: meeting people who’ve led an interesting life, and engaging with someone else’s story, can be fascinating – an education. Conventional authors need to undertake research at their own expense; as a ghostwriter you get paid to learn some amazing facts and stories.

To be sure, there is the constraint that you can only go where there is a budget, rather than have the freedom to research an area of your choice. In practice, however, this can lead you to fascinating stories, and whole worlds, that you didn’t know existed.

And you get to work in a team. You look forward to the next meeting with your client, and the stories that they will tell you. So while the initial impulse to earn a living through ghosting may have been force of circumstance, there comes a point for some that we make it our career as a positive choice. For the client, this means that you working with an experienced and highly motivated professional writer for whom penning other people’s stories is a dedicated profession, not a side-hustle.

I think I can say, honestly, that if the earnings from my handful of non-fiction titles or three novels were to take off – say, through a dramatization, while I would be delighted I would not give up ghostwriting. It’s way too interesting.

• Philip Whiteley is an author and ghostwriter, who pens fiction under the byline PJ Whiteley. There is more information at pjwhiteley.com