The fact that a wine has sediment or "least" is not necessarily an indicator of quality. Sediment in wine can be the result of a natural aging process and can be a sign that the wine was not filtered before bottling. Some high-quality wines, such as bottle-aged red wines, can develop sediment over time.
However, sediment can also be the result of a flaw or error in the winemaking process. For example, if the wine has been processed incorrectly or if it has become contaminated with bacteria, an unpleasant sediment can develop.
In general, the presence of sediment should not be used as the sole indicator of wine quality. The quality of a wine depends on many factors, including the grape variety, the region of origin, the winemaking techniques and the age of the wine.