Most people in research probably have first-hand experience regarding how difficult it is to get some people to reply to emails, e.g. (but not limited to) some reputed professors. It is also difficult to establish how to interpret a lack of response, because the person can be just busy and miss your email (i.e. "save for later" then forget about it) or might be purposely ignoring the email. I find the lack of response particularly annoying when contacting a listed "corresponding author" about their paper.
I have experienced several extremes: professors who reply within hours (or even minutes!); professors who failed to produce any response at all; even once I sent a job query and didn't get a response until after 2-3 months later, when the professor apologized about forgetting to reply and said he was very interested in my application.
The latter case almost cost me a job (luckily I had already secured a position elsewhere), and as it turned out later I could have resolved the situation by sending the professor a reminder that he had not replied to my earlier email. But how could I have interpreted his lack of response as either forgetfulness or disinterest?
The situation is usually better with postdocs and graduate students, who tend to reply, and when they do their replies tend to come faster.
Hence, my questions are:
- How to improve the chances of getting a reply to one's email besides the obvious "be brief and to the point"
- How to interpret the lack of response
- When is it appropriate to send a reminder and tips to avoid annoying the recipient with it
Edit upon request:
The typical content of the emails I'm referring to would be regarding the work done by the email's recipient or at their lab (questions about papers published by them, for instance). Non-spam job applications or surveying possible collaboration could also be included here.