seems like they always get hyped up and always tend to fall short Odlanier Solis, Luis Ortiz, Frank Sanchez. These guys are often hyped up then they get "exposed" or get defeated and never really reach the top level this is more prominant in HW, where they don't nearly achieve the same success as they do in the lower weights?
All three of your examples were also fat. The amateur system in Cuba teaches skill, but apparently not discipline. Once they get a taste for American cheeseburgers, there's no holding 'em down.
What you see when many of them get their chance is that they are not fit, certainly not fit enough to compete at the higher end of professional boxing. Solis wasn't fit for the Vitali fight and he got stopped extremely early. Luis Ortiz lack of stamina cost him the title vs Wilder, he was probably one combination away from stopping Wilder but gassed out at the crucial moment. Those are two high profile examples. The other thing is that the successful amateur style over the years has often resembled "tag" or "you are it", and with HW boxing as a professional you need to land heavy shots regularly to be successful. The Cuban HW's spend a lot of years from a young age as an amateur and its difficult to reprogramme themselves to fight in a style effective for professional boxing. In fact very few are capable of adjusting to professional boxing who were higher level amateurs for a long period of time in general. Staying amateur for too long is a bad idea if you want to make payola as a professional boxer at the highest level. But in Cuba being an amateur boxer is probably very well paid relative to other professions so they stay on too long.