For instance, with Google, if when you first set up your custom domain you didn't set your Google Apps account to auto renew your registration (i.e. they take the money out of your bank account automatically), and you let your account expire -- even if it is for legitimate reasons, such as temporary money issues -- then there is no quick and easy way to get your domain name back. The company starts using your domain name for junk advertising -- in other words, it becomes wasted space -- and there is nothing you can do, unless you are willing to pay substantially more money to try and buy it back by back ordering it through a site like eNom or GoDaddy. If you registered your domain with a company like eNom or GoDaddy through Google, and you had a free Google Apps account (from when they were free), you can't access your account to go back on and renew the domain name of your website or reset it to automatically renew.
Not being able to renew the domain name (without paying a lot of extra money) that is associated with you is especially bad news if you are trying to get your business started and you are paying for everything with whatever spare money you can manage to put into it. If you are a college student or are working another job to try and make ends meet while trying to set up your own business on the side, and you don't set your domain name to automatically renew because you don't know if you will be able to spare the extra money, and it expires, it will be devastating to your business. Especially if you can't afford the cost of getting your domain name back when it finally does go up for auction.
People will try to find your website and the URL will instead take them to the junk space with your name attached to it and it will destroy any little credibility that you might have had. And your business will be dead and you will have to start over from scratch, and any work that you might have put into it is all for nothing.
The way domain names are registered and controlled by large corporations is a scam and only they really benefit. People have dreams and those who work towards pursuing them have to overcome increasingly insurmountable obstacles to even catch a distant site of some distant valley which may or may not contain their goal. The whole concept of the American Dream is a nightmare for most people.
And forget trying to get help from the companies. They have made it next to impossible for anyone to receive anything even remotely resembling what most people would consider customer service. The corporations do nothing but send people around in circles, until they are so dizzy and frustrated that the people give up and move on and leave behind those insignificant, unrealistic dreams.
The reality is that it is impossible to "pull yourself up by the bootstraps" (which is what most people are trying to do when they start a business). If you want to get ahead, you have to let some large, faceless corporation pull you up and shake you over a pot until every little penny in your pocket is gone, and then, and only then, maybe they will help you. But only if they feel like it.