Why don't people just stop payment? I remember when an insurance company tried to not let me cancel. I copied some boilerplate termination letter from the internet, and blocked payments from my card. They cancelled very quickly. Then again this is in the USA, so Germany may work differently.
In Germany if you have a contract which binds you for a certain amount of time, blocking the payment will just result in letters, extra fees and eventually collection agencies and a state bailiff. This will not just put a stain on your credit score but might also get you into legal trouble.
There are multiple reasons. You often don’t subscribe by credit card but by bank account (you authorize them to pull money from your account). This means you cannot cancel, only the company can cancel. If you want to cancel you must hire a 150€/h lawyer to take them to court and fight a lengthy lawsuit that you will lose. If you did subscribe by credit card and block it, they will hunt you down to the last cent. They have the lawyers and debt collectors while you don’t.
Sure, debt doesn't just go away. But there's no loan, so why are you talking about debt? The grandparent comment is talking about online subscriptions. If you stop paying your your subscription, then they'll terminate service. Likewise if you stop paying your insurance premium you won't be able to file any claims. But unpaid subscriptions don't magically become debt.
If you don't pay your electricity or water bill then that's a different story because utilities are not allowed to just stop service for things people's lives depend on. But utilities are more heavily regulated than normal subscriptions. For the most part, if a company tries to keep you from terminating a subscription and you say, "well, I'm not paying anymore. Do you still want to keep providing the service for free?" it's an effective way to get them to terminate service.
So if you block your Netflix payments you really think there going to send debt collectors? No, they'd lose more money on hiring a collector than they'd gain back from recovering one month's subscription.
They probably could and I'm assuming they would just sell it to a collections agency for pennies on the dollar and the collections agency would just send an automated notice hoping the person would pay it. For example, I had wave internet in seattle and when I moved I obviously canceled. They screwed up setting the cancellation date though and ended up charging me the next month. Just got a collections notice for that 1 month of charges. I messaged them and apparently there is nothing they can do from their end at this point so now I'm disputing it with the collections agency.
Pretty dumb on their part if you ask me considering now I'm telling everyone not to use them because of their screwup and the fact that they would sell it to a collections agency over 1 months worth of payments.
Like the other person said, here you have to explicitly end your subscriptions. Stopping payments will not end your subscriptions. You'll end up dealing with collection agencies.
Unless the company values their public image and return customers more than a small payment, which thankfully is the case for many. I just wouldn't count on it, ever.