Over the years, there have been a fair number of folks, mostly “managers”, who suffered from the habit of reading the first couple of lines of an e-mail and then responding. In many cases, this meant that the response was not on point or useful and follow up e-mails were then required. This naturally frustrates the original sender and wastes a great deal of time. (As an aside, these were often the same folks who had no clue what a subject line in an e-mail is for and either used a generic term which did not accurately describe the subject or changed the topic of an e-mail string without changing the subject line.)
Of course, as annoying as the above habit may be, some folks manage to make things even more difficult by making responses piecemeal as they digest the original communication. This approach tends to result in confusion, changing answers, and lots of irrelevance. Once again, this wastes time unnecessarily and continues to frustrate the original sender.
What might improve the situation could be an approach where the recipient who does not have the time or desire to read through and understand a communication sends a brief response acknowledging receipt and no more. Naturally this will require a follow up by the recipient to actually address the content of the communication but will allow some additional time to do it right. A fault with this approach is of course the person we all know who on receipt of your e-mail communication knows without reading it fully exactly what you are thinking and what the appropriate response will be. This person is unlikely to ever read or attempt to understand what you sent and so most any response is likely to be worthless.
Oddly enough, if one takes the time to read and understand a communication before responding, much time will be saved and frustration avoided. The sender might even end up believing that you respect his or her communication or at least the job at hand. And if you don’t take that time, remember that it may end up causing you more frustration than you caused the original sender.