I've said quite a lot on this topic in other threads concerning day/night cycle and weather, so I'll just add this: it makes the world so much more believable and alive. Immersive. I don't know how many people here played it, but for me implementation of time passage was great in the first Witcher game. It was very much eurojank, but it had an amazing atmosphere, and a part of that was how the world changed with time. A lively (if very troubled and quite grim) city became different at night - it made you uneasy and wary of whatever creature may have been prowling the night. City outskirts, populated by hard-working people during the day, turned dangerous after nightfall, when all sorts of monsters (sometimes in human form) would crawl out. The music (excellent in this game) reflected this very well. And the weather - once it started raining, all the people rushed to flock under any roof they could find. Townswomen took joy in spitefully wishing it would rain on their neighbours' laundry. The world felt alive, not as a setpiece - and it was a game that had to overcome many technical challanges.