This is a terrible design. The bowl is quite shallow, so the water level sits quite shallow as well. Think about it. There isn’t a lot of room for solids, inotherwords. Also, this shallowness of the bowl design and the flush mechanism does not permit an adequate amount of incoming water to create a vigorous flush. The bowl is frequently remains soiled because there is simply not a lot of water swirling after the flush. The suction mechanism even occasionally causes a bit of a droplet to splash back upwards!  We had a plumber come in and check to see if anything could be done to improve the installation.  It’s poorly thought-out by designers who don’t actually use their own products. It also has a separately sold bowl brush cleaner which oddly is fairly miniature in size. I guess this is sold because the company realized that the bowl is not left clean most of the time. Ridiculously bad for such an EXPENSIVE product.