What is a Derivation Path?

Few people know this, but BIP 39 was actually Nack'ed by the code reviewers. In the Bitcoin core repo, to Ack is to agree with the proposal. It means you reviewed it and gave a thumbs up, this is good code. In BIP 39's case, it got a Nack from reviewers which means they reviewed the code and gave it a thumbs down, this is bad code.

BIP 39 is where we get seed phrases from. So why was it negatively reviewed? Let me put it this way, do you know what a derivation path is? If you answered no, then you have the answer to your question.
Comments:BIP 0039 · bitcoin/bips Wiki (github.com)

Now, getting a Nack in your BIP doesn't mean its dead forever and ever. You can update your BIP to address the concerns and change that Nacks over to Acks. However, wallet developers implemented the BIP before any improvements to the BIP were made. That means that things like the derivation path can be wildly different between wallets.

You can check which derivation path your wallet uses here: https://walletsrecovery.org (this is literally just a list of derivation paths)

What makes this worse is that things like timelocks can not be represented using BIP 39 because it uses a locking script and that script needs to be part of your backup. That's why something like Liana wallet uses a different backup method called "descriptor wallets"

This is the BIP for descriptor wallets bips/bip-0380.mediawiki at master · bitcoin/bips · GitHub

So look out for this new wallet recovery type. Maybe even you can think of ways to make it easy to use for the general community and it may as a result even take over seed phrases.