Why does weight lifting strength atrophy quickly and take longer to recover?

Hi all, I maintain an even/balanced body weight through the year and maintain my muscle tone. And sports that I only can do seasonally (surfing, skiing, mountain biking) only seem to take about a week or so to get back to where I was at the end of last season; even after say 6 months of not skiing, 4 months not mountain biking, 3 months not surfing for example. The first few days back are always a rude awakening, but after that it takes little time before I'm progressing again and I find these activities to be just as challenging as lifting weights for different reasons. Yet when it comes to weight lifting strength; I find taking as little as 3 weeks off lifting to be a very significant set back that takes weeks or more to just recover from. Why is this? I didn't find the right solution from the internet. References: https://forum.bodybuilding.com/showthread.php?t=174968921