It’s understandable to not see the need for it during winter, but for the sake of it working in the summer, use it or lose it. As explained in a previous blog, using the aircon is actually a very effective method to defog a windscreen anyway.
As such it shouldn’t be such a burden to use it occasionally during the winter months which should keep everything from seizing up. This stops the horrible realisation, when you use it for the first time on the first swelteringly hot day in summer, that you’re just pumping the same hot sweaty air round your car.
When you don’t use your air-conditioning, the aircon oil sinks to the bottom of the system and leaks out through the seals. Over time it all leaks out and ruins the seals.