Five things that make good illustration

Originality/Tone of voice

Jack Teagle

Luke Pearson

Tom Gauld

Ping Zhu

Robert Crumb

Narrative

Jillian Tamaki

Jason

Stephen Collins

Chris Ware

Glyn Dillon

Exciting/engaging imagery 

Tove Jansson

Nick Edwards

Jon Klassen

Pia Bramley

Scott C

Conveying an idea or concept

Adrian Tomine

Jean Jullien

Joe Sacco

Kelsey Heinrichs

Jim Stoten

Choosing style and media to fit a concept

Ghost Shrimp

Holly Wales

Nicholas Delort

Lizzy Stewart

Eleni Kalorkoti