Every link's text must describe where it goes. 'Click here' and 'read more' fail screen-reader users who scan a page by jumping from link to link.
WCAG 2.4.4 — Link Purpose (In Context) (Level A)
WCAG 2.4.9 — Link Purpose (Link Only) (Level AAA)
Accessibility Checker — Ambiguous Anchor Text
WP Accessibility — Content and images: Links