Where does the term "bucket" in cloud storage come from?

Solution 1:

It appears the the term bucket is just a generally accepted metaphor:

In computing, the term bucket can have several meanings. It is used both as a live metaphor, and as a generally accepted technical term in some specialised areas. A bucket is most commonly a type of data buffer or a type of document in which data is divided into regions.

Bit bucket:

This is a humorous but common phrase. Something goes into the bit bucket when it is deleted, generally irreversibly and quite often wrongly, such as files or emails that just disappear.

It has been commonly suggested that this usage dates from the days when punched cards and/or punched tape were common. Card and paper-tape punches each had a receptacle for the chips punched from the cards or tape to create the holes (rectangular in a card, round in a paper tape), which often looked like a bucket and was known by this name. By analogy it was jokingly suggested that the CPU, which in those days was an equipment rack of similar size to a large peripheral unit, contained a similar receptacle for lost data.

(Wikipedia)