"the reviewing court, after assessing the evidence in its entirety, is left with a definite and firm conviction that a mistake has been committed." Krys I. Lufthansa German Airlines 119 F.3d 1515, 1523 (11th Cir. 1997). See also United States I .United States Gypsum Qcs, 333 U.S. 364, 395 (1948) (explaining gene