Many instrument-rated pilots struggle to maintain their proficiency for IFR. Logging the six approaches, holding procedures and course intercepts/tracking required by FAR 61.57(c) can be quite the challenge for pilots who fly infrequently or who are based in regions where good weather is routine. Simulators and training devices can be major boosts to maintaining proficiency, especially when focused on maintaining instrument scanning skills and practicing IFR procedures. But when it comes to flying personal aircraft in the clag, there's nothing that beats practicing in the real thing.
This is a companion discussion topic for the original entry at https://www.avweb.com/flight-safety/technique/ifr-practice-approaches