If you have worked with us before, you will know that we always stress sending along a thank you note after your interview. Emailing it first and if in person, sending it snail mail. What the clients are looking for is an honor of tradition but what sets you apart is that you took the time to write something substantial. It doesn’t have to be long but it has to be BRILLIANT. This is your writing sample and part of the interview process.

https://www.reuters.com/article/us-money-jobs-thankyounotes-idUSKCN1Q81FH