The price of convenience (proprietary connections)
Have you ever tried to cancel a gym membership? Some want you to cancel in person, sometimes online, rarely over the phone. They'll certainly try to sell you a discounted plan. And you can expect to pay a hefty cancellation fee.
Chargers for electric razors or electric flossers rely on specially designed proprietary connections to ensure the optimal flow of voltage to their batteries.
But chances are your printer only takes their brand of ink cartridges. Your Keurig accepts only K-Cups. Your Tesla only charges with Tesla chargers.
And if you want options beyond that, you'll have to navigate through an expensive labyrinth to get out.