Here's why it happens:

A lot of the time the datastructure you pass into writeAPI(obj) is different from the datastructure that is returned from readAPI(obj) -- even if the information contained is the same!

No one wants to do that data structure transformation and potentially miss an edge case/break some implicit assumption about the data structure some fuckall downstream consumer has.

However it is already done in the readAPI() function. So latency and throughput be damned, let us do:

  writeAPI(objects)
  objects = readAPI(objects)