endeavor, strive, encourage, cut
釗 centers on applying force with a sharp edge: cutting, carving, or scraping away. The extended senses of endeavoring, striving, and encouraging come from the idea of persistently cutting through obstacles.
釗 combines 金 (metal) and 刂 (knife), suggesting a metal cutting tool. The exact historical development is uncertain, but the component structure points to cutting or scraping with a metal blade.
A metal (金) knife (刂) is used to cut and carve. Picture a craftsman persistently cutting metal, striving to shape it—this effort embodies endeavor and encouragement.
For ショウ, imagine a metal knife cutting through a showy piece of armor: show -> ショウ, and the blade carves through the metal.