Companies break promises all the time. A self-guaranteeing promise does not require you to trust anyone. You can verify a self-guaranteeing promise yourself.

File over app is a self-guaranteeing promise. If files are in your control, in an open format, you can use those files in another app at any time. Not an export. The exact same files. It’s good practice to test this with any self-proclaimed file-over-app app you use.

“Stainless steel” is a self-guaranteeing promise. You can test it yourself on any tool that makes this promise, and the stainlessness of the steel cannot be withdrawn.

Terms and policies are not self-guaranteeing. A company may promise the privacy of your data, but those policies can change at any time. Changes can retroactively affect data you have spent years putting into the tool. Examples: Google , Zoom , Dropbox , Tumblr , Slack , Adobe , Figma .