Some of the better posters from the last few years are from pretty lousy movies. Nurse, Rubber, The Great and Powerful OZ as examples. All good posters. The movies not so much.
A bit OT, but if you want a very interesting movie experience first watch
Oz, The Great and Powerful (which I liked), then the '39
Wizard of Oz, followed by Walter Murch's
Return to Oz.
The coolest inadvertent trilogy evah.