That's definitely true. I've been tempted to write a rant about how many articles and comments (e.g. on Reddit) talk about how that is part of the "golden rules" to securing good work, but then scoff (yet again, on Reddit and other sites) at people who get frustrated at the realization that you don't just find a niche and instantly get higher salaries or contracts.
I actually did market myself briefly last year as an API developer (coincidentally with Django, but I use Vue instead of React). I'll be honest though that it was tough just because I thought I had to market myself to other technical people, and in my experience, non-IT departments have more budget and flexibility, so I had to speak about APIs from a line-of-business point of view. But marketing and data science are very compatible, so that's an easier way of bringing it up.
Actually, I understand why you said that. To me, niching is just a starting point.
Which you have to hustle by selling, marketing & networking yourself as an expert in that specific niche for referrals.
One of the areas is networking which so far I founded Jordan Harbinger's 6 Min Networking to be really good especially his podcasts.
It takes tons of action, reflection & learning which will help you well if you plan to go for the entrepreneurship route.
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