Today I suddenly found that my email server requests a read receipt every time when I send emails. Since I am recently exchanging messages with a potential Phd supervisor, I wonder if this will make him feel that I am rude and annoying? I have already turned this feature off!
Unless you have reason to suspect that emails are not being delivered successfully, email receipts are pretty much useless. Here's why:
Not all email clients support read receipts - Mail on OS X doesn't, for one prominent example. If some of the previous emails you sent requested a receipt, and it wasn't returned, obviously either the prof's email client doesn't support it or he didn't bother clicking that button.
Unless the receipt is returned, you can never be sure if the email was read or not.
Unless the email is replied to immediately - which is unlikely if the reply will take some effort - it can easily be forgotten about. Receiving an email receipt is no guarantee that you'll get a reply.
If you have no response to an email after a reasonable period of time ("reasonable" can vary between 3 days and a month or more, depending on what is required), just send a quick reminder email.
Unfortunatly, this is highly subjective. I think everybody could clearly understand the benefits of a read receipt this is why all modern messaging platforms (Whatsapp, Telegram etc. etc.) implement this feature automatically. I could not estimate how many times I encountered the dilemma of "should I send the email again" because sometimes it happens to lose the email even though this is not in the spam folder. For me, this communication issue should be solved somehow and I would not consider rude a person trying to solve it with the means that he has. In my personal opinion, I would not consider it a bad practice unfortunately many people prefer to lose or not answer emails rather than face the writer with a clear answer. I think that a messaging platform should be a way better tool to use in the future for communications between persons.