Is it Compulsory to give name(to Baby) according to Rashi (राशि) in Hinduism ?
In earlier days, people doesn't used to record the day of Birth, even if they do many are not educated enough to remember those 60 Lunar years (after which it is believed in Hinduism that we would have similar years).
So, naming after the nakshatra/rashi helped them track things, without having to search through documents available at the village intellectual.
These days, I have seen people keeping a middle name based on nakshatra & dropping it in official records.
Regards Narendra N