On a new build the buyer (or a professional snagging inspector) walks the unit and documents every defect against the specification: misaligned doors, poor paintwork, cracked tiles, non-working sockets, plumbing and HVAC faults. The list is submitted to the developer to remedy under the build contract.
In the UAE snagging is a recognised step before the final handover and DLD transfer; developers typically give a defects-liability period (often 12 months) plus longer structural warranties. In the UK new builds carry an NHBC or equivalent warranty, and the first two years are the developer's responsibility for defects.
Buyers should snag thoroughly before signing handover, keep dated photographs, and hold the position until major items are fixed — leverage drops sharply once handover is accepted.