I was at first disappointed on how soon I needed to replace my filter. But, I think I replaced my first filter sooner than I needed to. At first, the flow through the filter is relatively high. Over time, the flow gradually diminishes. But, I discovered that the flow seems to stabilize at a trickle. The trickle actually works for me. I refill the pitcher when I don't expect to pour any more water for a while (because the pitcher does not pour well when unfiltered water is in the upper reservoir). Using this approach, I can keep the pitcher mostly full on filtered water most of the time.
I ordered a new filter about 5 months ago expecting to, soon afterward, replace the old one (which had 4 months of use on it), but I am still using the old filter. Depending on how much filtered water you use, you might want to keep this in mind.