This is where training discussions get messy, because many people have their own idea of what "correcting" means. I correct my dog all the time--verbally. And I withhold rewards (negative punishment), like a toy or treat, if they don't do what I know they know how to do (a fully proofed command). If it's still a work in process, then a very mild "nope, try again" is all I give as a "correction". But most people view corrections as leash pops, scruffs, alpha rolls, etc. aka "physical punishment/positive punishment" and that's where the trouble (for the average pet owner) starts.