Same question to you ? Why don't you call it different bitcoin addresses instead of accounts. Like in Electrum you have many addresses including the change address. We don't call them accounts. I hope you and me are on the same page
We need a way to differentiate between addresses of the same wallet and addresses of two completely separate wallets. They are all addresses, though. In your example with Electrum, you are talking about one wallet. Let's call it Wallet #1.
Let's say you have a business or hobby that pays you in bitcoin. You could use Wallet #1 and all its addresses to receive payments for that. That's what wallet #1 will be for.
Remember, Bitcoin has a public blockchain. Anyone can check the ledger and see the history of UTXOs. Why is it a good idea to create a second wallet or a second bitcoin account? Because you may not want to connect your business coins to other types of bitcoin activity. For instance, if you are gambling, or like me and you, we participate in paid signature campaigns. Your wallet #2 with a completely different set of addresses could be used exclusively for your gambling.
That way, there is no way to connect those two activities like when you consolidate multiple inputs into one. If you only used one wallet, you would end up with coins from your business, your gambling, something you bought on a CEX, your signature earnings, some sats your friends gave you, etc., all in the same place. If you create multiple bitcoin accounts (wallets), that would no longer be a problem, unless you intentionally connect them. It's better for your privacy and separating different activities.