Reviewers are usually people who would have been, poets, historians, biographer, if they could. They have tried their talents at one thing or another and have failed; therefore they turn critic.
There is a difference between responsible criticism that aims for success and defeatism that refuses to acknowledge anything but failure. Hindsight alone is not wisdom, and second-guessing is not a strategy.
I lose my patience, and I own it too,
When works are censur'd, not as bad but new;
While if our Elders break all reason's laws,
These fools demand not pardon but Applause.