Every single person who runs their own business effectively works on 'zero-hours' 'contracts'.
It's called making sure you do your marketing effectively and making sure you have a robust sales process and a solid product and all the other things you need to not rely on somebody else bailing you out when you take a sickie.
So that would include around 5.4m 'sole traders'.
We like it (those of is that run our own businesses and those of us who are sole traders) - because we're our own boss and don't have anybody telling us what to do every day. No manager. No 360 reviews. No HR department sticking their noses in. None of that.
Sure the price is making sure you get ahead of the game and save enough for a rainy day - good old-fashioned values a few of the snowflake generation could do with learning.
What a load of self congratulatory tripe and you are being deliberately misleading at the cost to you.
So you manage to combine all those functions of Marketing, sales and have a solid product?
In business you are tied hand and foot to the fate of the business in reality, it owns you body and soul 24/7 365 days a year
Unless you are playing at it as a hobby and you want to regularly go bankrupt like Trump and have to be bailed out by Daddy.
There are old and there are bold business men , but there aren't many old and bold ones.
Most end up having to work for someone else.