The idea of "Sparks" is borne out of the fact that to some couples, their marriages has become a routine, with little or no fun or excitement.
This is occasioned by a lot of factors, one of which includes (but not necessarily limited to) the general economic situation of the country vis-a-vis the desire to make ends meet, hence causing couples to focus more on Work, Business, Career, Welfare of the family, Raising the Kids, etc. while the romance in their marriages gradually fades away.
The implications are that consciously or unconsciously couples begin to drift away. Marriage is fun and both parties must collectively, consciously and intentionally put in efforts to keep the romance and fire burning in the marriage.