There is a culture in India that before marriage this is very important to match the horoscope of bride and groom. If horoscope mismatches then you can get married to that person or you have to think twice.

Is marriage really depends on the horoscope, is position of Venus will tell us your marriage will work or not!!
Actually astrology doesn’t impact on success of your
marriage. The positions of stars nothing to do with marriage these signs can impact
how you feel about things. You must be thinking that scientist must be the
right person to answer all these questions. The university of Manchester analyzed
10 million marriages, using census data from U.K and inferring astrological
signs from couple’s birth dates. The university team found that, in reality,
people tend to marry other with closer birthday to their own. It turn out that
these same birthday pairing are probably just accidents on the forms.This research shows that astrological sign has no impact on
the probability of marrying – and staying married to – someone of any other
sign.