I aspired to concision because I believed I wasn't an interesting person and didn't deserve any attention outside of the little I'm able to grab, so I kept my writing pithy in the hopes that I wouldn't have to "take up too much of anyone's time/attention".
Unfortunately, too much concision can lead to short pieces that are tiring to read -- your brain has to work harder to fill in the gaps. Sometimes "unnecessary" words are needed to help the reader feel more comfortable. Not everyone is an engineer or a technocrat. Parsimony isn't always a virtue.
There's is a place for concision, but I now believe concision is the wrong goal to aim for. Often the real goal is to create an emotional connection, and if it takes a few more words to achieve it (without belaboring the subject), so be it.
People -- often teachers -- think good writing is solely about effective communication -- to me, there has never been a wronger conclusion than this.
Voice elevates an informative essay from a dry recitation of facts, offering the reader little of genuine interest, into a conversation in which the reader is able and welcome to participate. Voice also offers interest of its own, which can help sustain a reader through what might otherwise prove intolerable complexities or difficulties in the subject matter of the work.
You may, of course, consider this, and consider the virtues of the Hemingwayesque ultimacy of concision, and decide that the latter outweigh the former. I don't agree, but we all ideally write in our own ways. I would, though, ask that you do consider those virtues - and their contrary vices - rather than partake of the blind veneration of Hemingway so common among the rather dim luminaries of modern literature.