No. You do not need to postpone every marriage decision until a supposedly favourable Mahadasha or Antardasha begins. In Vedic astrology, these planetary periods are traditionally used to interpret the timing of different life experiences, including relationships and marriage.
If astrological timing matters to you, consider it alongside relationship compatibility, emotional readiness, shared values, financial circumstances and family expectations. Avoid rejecting a healthy relationship solely because of an unfavourable prediction, or rushing into an unsuitable marriage because an astrologer identifies a favourable period.
The quality and suitability of the relationship should remain central to your decision