A meta description is a short blurb about the particular page of your website. This is a great place to insert keywords easily. However, you also want to include helpful information for potential site visitors to draw them into clicking on your website. This blurb will appear in search engine results pages under your H1 title tag and URL of your webpage.
Remember when you used to rely solely on search engines for traffic? Remember when you worked on SEO and lived and died by your placement in Google? Were you #1? Assured success. Well, okay, maybe not assured. Success only came if the keywords were relevant to your site users, but it was the only real roadmap to generating site traffic and revenue.