Thread count is one of the most mis-understood feature when buying sheets.

We have been typically lead to believe that the higher the thread count, the better the fabric, right?  In reality, thread count is used more as a marketing term by brands and not as a reliable indicator for bedding quality. 

There are only so many threads that can fit into the measurement area without making an overly dense sheet.  Brands are now using multi-ply threads whilst claiming each ply in the thread counts towards the thread count. For example a single thread might be four plies twisted together; one manufacturer will call that one thread, while another manufacturer will call that four threads. How can the consumer tell the difference?

Single ply typically caps out at around 400–500 threads. After that, manufacturers have to use two-ply thread. Thread counts of 800–1000 or more likely use multi-ply threads which are more expensive and less durable with limited benefits. Yarn quality and weave type are also just as important as the thread count.