Comparisons are as bad as cliches too. Contractions aren't necessary either. Be more or less specific. Don't be redundant - don't use more words than necessary because it's highly superfluous. Tell me what you know.
Exaggeration is a billion times worse than understatement.
Analogies in writing are like feathers on a snake. Even if a mixed metaphor sings, it should be derailed. Always sue a spell hcecker.