When it started in the as family Bank and later local (in Santander) and regional Bank they were really impressive. Then in the 70s they did tart to become national and suddenly they were less impressive. And I know what I am saying because a that time their were poaching staff from other Banks (that in less than 6 months they were regretting it) and I was working in other Bank in front of their local branch. Fortunately, I did refuse their offer.
Mr Botin family always was a local mafia so nothing new on that, His son-in-law is Severiano Ballesteros and is the only thing good in that family.
My sister is going through a legacy issue were the money is deposit in the Santander and after 10 years still she didn't manage to get a cent. Every time is a new legal demand; three lawyers have been involved so far unsuccessfully.
They charge the Moon nearly just to get in a branch (it s joke, of course, but it is pretty close) and to breath inside. To open a new account by transfering the standing balance from the old one they charge you. It is the Bank with more expensive fees in the country to use their ATMs. Customer Service is in fact non existent, when you go to resolve an issue they treat you like if you were a cockroach; if you call by phone always "sorry, in this moment there is not staff available, please call later".
I could write a book about Banco de Santander bad behaviour..