Why don't people return from Bermuda triangle?

I don't know why you should think that no one returns. Hundreds of thousands of people visit and return from Bermuda, Peurto Rico, the Bahamas, and Miami Florida each and every year. All of these tourist attractions lie within the 'Bermuda Triangle' and all of them rely on these thousands of tourist for their economy. If more than the average number of people did not return, this area would not be as popular as it is and has been for many decades.