Dellacroce was feared and respected, but he wasn't all that smart. Like most Mafiosi, he had a "legitimate" job that gave him a source of income so he could pay taxes and escape tax evasion prosecution, which has sent more mobsters to jail than RICO and drugs combined. Also like most Mafiosi, Dellacroce was greedy and arrogant--and regarded paying taxes as stuff for saps. His "legitimate" job paid him only $10,000 a year, way below the Federally established poverty level. So, when he lost $100k in a Puerto Rican casino, the Feds had no trouble convicting him of tax evasion. He went away for five years, during which time Gambino took to his deathbed. Had Dellacroce been free at the time, he might have been named successor.