Most relationships in which a tally is kept to see who owes who this or that are doomed to failure. True relationships while mutual are good because they are mutually desired and not a transaction of a favor for a favor.
It is often that the modern scheme of networking for advancement has the affect of creating a massive number of relationships of no meaning. The relationships mean something only in so far as their utility or perceived potential utility.
True relationships are not based upon utility but rather love. Love is of course a Christian virtue while relationships based on utility is a virtue of the world in every age.
Love does not keep a tally. If love did keep a tally it would not care that there are those who one cares about who will surely default in a sense of equal utility.
You see this act of kindness which is done with an expectation of a return act of kindness is a worldly virtue and not a Christian one. In Christian virtue kindness is often given with no expectation of return.