It depends on how you define "lose". To keep all your data for a long time takes effort. Storage formats change. Disks die. Hosted storage bills need to be paid, billing needs to be updated (credit cards expire), etc.

You really need more than one copy in more than one place if you want to be really confident that your data won't be lost.

Is all your data worth the effort? Is it healthy to try to hang on to everything?