Shows Professionalism – gratefulness and courtesy is a proof of professionalism.
Strengthens your interest: It tells the hiring team that you are truly enthusiastic about the role.
Your subject line is the first part of your email that the interviewer sees, and can determine into which buckets they dump you.
Contents of a thank you email
First Line: Begin with a warm opening. However, if you do say something to the camera — speak directly to us and thank us for our time.
Human touch: Cite something specific they said during the interview demonstrate that you are an active listener. This may be specific information about the job, organization culture, or an idea passed along during the interview.
Proofread: Make sure your email is error-free. If the message is poorly written, it can put a damper on your thanks.
Tailor Your Message: Message the interviewee back and forth if you talked to numerous individuals.
With a professional approach: Although you should also show your enthusiasm Steer clear of overly informal language.
Also, if the interviewer was being be very formal, respond with some formality as well. Should they be more casual, you can also be a bit more casual but not too informal.
Be Specific : Sending a standard “we appreciate your time” type of email which references nothing in particular about the interview, just yells “form letter”.

Never hard sell: While you should demonstrate that you are interested, do not look desperate.
Not Too Soon: sending the email immediately afterwards looks like you slapped it together in haste afterward.
Do Not Discourage Salary or Benefits: One major don’t is not to discuss salary or benefits in the thank you email. You are supposed talk this later stage of the whole negotiation.
And do not forget that the subject line as equally important as the content. Select one that shows you are organized, well-mannered, and expresses your gratitude for the chance.