This is explained partially by the Four Point Scale. [TVTropes warning]<p><a href="http:&#x2F;&#x2F;tvtropes.org&#x2F;pmwiki&#x2F;pmwiki.php&#x2F;Main&#x2F;FourPointScale" rel="nofollow">http:&#x2F;&#x2F;tvtropes.org&#x2F;pmwiki&#x2F;pmwiki.php&#x2F;Main&#x2F;FourPointScale</a>