Inheritance. For most of us, it's not a priority but it will be a concern eventually. We want to ensure our loved ones are taken care of after we kick the bucket. It's somewhat straight forward with fiat money and common assets (home, investments, property, etc). But with cryptocurrency, it's a bit less straightforward. It is financial self custody. No one is holding your money but you. Third parties are non-existent (unless you're actually using a custodial service to hold or manage your coins).
Lately, we've heard of people generating a new seed phrase for every new wallet they use. By "wallet", we are referring to the "brand" name of wallet software or hardware. If this is you, you don't have to do this. Your seed phrase (or your coins for that matter) isn't tied to a specific wallet.
If you've generated a new seed for every wallet you used, you might in a situation where keeping track of all those seeds is getting more and more difficult. You might be running out of hiding places, having trouble remember where they all are, tired of keeping track of which wallet holds what, etc. But what if you could have just one seed yet still have multiple wallets? You can.
Most popular cryptocurrency wallets use the BIP39 standard: the use of mnemonics to serve as your back up recovery seed in the event your wallet becomes compromised. This is also known as a mnemonic seed phrase, recovery seed, wallet back up, etc.
Like most people, you probably have your seed at home. Because why not, it's your home. It's the place you always come back to and feel most safe. So, why shouldn't your seed be safe as well. But every once in awhile, you think of the unimaginable happening.