Puerto Rico is a popular tourist destination and has been ever since the Americans began traveling for pleasure. Tourism is and was already in the 50's one of the country's main revenue. Naturally the hotels wanted their visitors to feel welcome and gave them exotic welcome drinks.
The welcome drink at the Hotel Caribe Hilton in Puerto Rico was served in coconuts and consisted of rum, coconut juice, lime and coconut cream. It was very popular, but the hotel was still forced to change the drink when the coconut pickers suddenly broke out on strike and it was difficult to get coconuts. And thus was forced to find another main ingredient, and also some other exotic way to serve drinks in.
The bartender Garcia managed to get over a large stock of pineapple and came up with the idea to mix the drink in them instead. This resulted in slight taste of pineapple, which he later chose to develop by adding chopped pineapple and call the Piña Colada. It is the chopped pineapple, which gave the drink its name. Piña Colada means is chopped pineapple in Spanish.
There are also early stories about a drink that should have contained about the same things, but the Caribe Hilton is the first recorded recipe for Piña Colada. It is from that recipe the modern drink originated.
Nowadays Piña Colada usually contains pineapple juice instead of chopped pineapple and it is a well-known drink that although it is mostly consumed in warmer climes it can be mixed by almost all bartenders.