So, do duvet covers need inserts? The answer is a definitive yes. The duvet cover, while visually appealing and practical, relies on the insert to serve its intended purpose The duvet cover, while visually appealing and practical, relies on the insert to serve its intended purpose The duvet cover, while visually appealing and practical, relies on the insert to serve its intended purpose The duvet cover, while visually appealing and practical, relies on the insert to serve its intended purposedo duvet covers need inserts. Without an insert, the cover would not provide the necessary insulation and comfort that a duvet is meant to offer. The cover acts as a casing, encasing the insert and keeping it in place, ensuring even distribution of warmth throughout the night.