More Than A Single Purpose

(Or the stream of thought transpiring?) Purpose: A goal, plan, or motive guiding behavior. But human action is regulated by many purposes. Given the convenience of combining things or just the random convergence of separate agendas at times, they will intersect. Can the diversity of goals/plans behind specific acts be traced back or subsumed under a single overarching one ("theory of everything" for the individual)? Plus, it's not uncommon for people to really have no clear or articulated reason as to why they do some occasional things; research indicating that they invent a "story" afterwards, believing it then to have been the actual driving motive beforehand.

There's a vague similarity here to cases of causal indetermination (did the ball break the window, or was it the electrons in its atoms with the same charge repulsing each other, or was it the general properties of gravity or spacetime, etc?). Or even multiple realizability in philosophy of mind (several different physical patterns might result in the same mental state).

The problem of interpretation or its conclusion-generations: The "why/how" of what happened if different background models or approaches yield different conclusions/descriptions; or the possible folly of trying to settle on a single "cause" when multiple influences converged upon the target beforehand.

It seems that the only things we can exclusively state a single purpose for, are things that man creates himself. With that sole purpose in mind, although such things can have user-defined purposes as well.

If man didn't create the thing in question, then he can't, with certainty. Know it's purpose(s).

It seem as though, for any non-man-made thing, in order for it to have a purpose. It would have to have been designed for that purpose, or it would merely be coincidence, that it gives the illusion of purpose.