i dont feel this is uncommon nor should it be without knowing the purpose of a task one cannot understand its importance wthout knowing the importance of the task one cannot properly place it in their list of priorities  from a productivity perspective if a person is spending too much time on a low priority task that person is less productive likewise if a person fails to place enough importance on certain tasks the results can be catastrophic leading to damage to property injury to people and even death  sometimes the person training you isnt the person to ask why something needs to be done a certain way  if theyre a low level person they may not know  the person that trained them may not know et cetera ad nauseum ive seen it time and again in different fields that were based on manual labor the worker bees are all busy doing their tasks most never understanding why  it wont take long for the person that does know why things are supposed to be done a certain way to step out from the crowd  theyll probably be the person that you see everyone else approaching for answers  thats the person you need to talk to  it may take a little time to identify them if theyre not always around you  be patient theyre lurking around somewhere