Business Email Communication & Etiquette: How long is too long to reply?

I’m not sure why I am continually charged with helping people assert their needs when I haven’t been asked to do so. Is three business days really too long to get back to someone for non-essential communication when there has been no communication stating a need to get a message back in a certain period of time? When the message was unexpected or when there is a constant back-and-forth and the other person is not letting a day or two go by before they reply again (no, they are replying back in hours and expecting you to do so as well no matter what time they sent the message). Or when they contact on a Friday afternoon and on Monday afternoon they are bitching me out for being disrespectful and not getting back when it’s only been 24 BUSINESS hours that have went by?

When I need or want a response, what I do is ASK for one! I don’t wait until I feel disrespected and then negatively ASSume when someone didn’t get back to me. grrrrr

As far as weekends go, I have a life but not really… because weekends are all about work too for me but a different kind of work. And why bitch me out on a Monday about it? A traditionally busy and challenging day for people.

While I’m at it, why do people ASSume negative things then add a final judgement without checking if their assumption is true in the first place?? grrrrr It’s mind boggling.

For essential “time sensitive” correspondence or agreed upon turnaround time, I do get back to people within hours or 24-48 hours otherwise it can take some time because going back and forth with people (like text messaging but in emailing) doesn’t work for me when I have more than 25 people in a day to correspond with and that isn’t all I have to do. I need to earn a living and do not have a bevy of assistants at my call. grrrr

So, my question is: HOW MUCH TIME IS ACCEPTABLE TO GET BACK TO SOMEONE FOR A NON-SOLICITATED PIECE OF NON-ESSENTIAL EMAIL that has no time sensitivity.

In future I’m going to tell people IN ADVANCE that it could take 3 business days or more to return their message and if they want to follow up with me at their convenience (if there is a need or want) then they can do so at any time by the original method of contact but preferably by a second method of contact since the first might be the problem of non-communication in the first place (like their message when into spam or got deleted).