I did after I got the awareness of grammatical writings, the bending of words and to place them in almost correct order. That is essential to etc. describe a thing. To know them is as said essential because when referring to a chair or a house on the road, we need to know a specific house, or if we like to sit by the window in a cafe or something like it. We also need to be aware of it, when we refer to a city of something or streets in an area. A noun can of course be very important and once we get the understanding of it, we will apply it right away.
Verbs as we know them, is the action that describes something, like running, to climb. I believe you get the picture. The importance of them is just as nouns. I have recently and actually always asked myself, if it was a right thing to do to write them down, then learn them by bending them in a way. I think it would be too big a thing, then I have later decided to jot down words starting with a, then b, then c, and so on, even some nouns could be verbs in some cases.
Going for the additions in sentences, is other words as we know and use but do not think of them, the adjectives, and those are hard to spot if grammatical skill is not properly developed. I myself do not think of them when I write a text which I work on to change as I am writing every day on stories and manuscripts. The importance of them is the addition to the nouns and verbs and some other names for words as I have saved in my browser for study for later use.