Cycling year round? How do they continue to gain?

When you're on, do you get to a point where the gains stop? Sometimes it's after 6wks, or it could be after 10wks, I can't figure out what the variable is. How do these guys cycle year round and continue to gain?

I think changing doses as off cycle to many is a low dose and on cycle is a higher dose and cycle different types of gears through the year as to not saturate any one receptor site with a constant type of gear, and ofcourse the all important keeping calories high and ur likely to keep gaining, maybe not like you did in the start of it all but lean muscle mass of a few pounds a year is all a seasoned vet asks for and can acomplish, just my opinion bro

changing compounds ever so often, like evey 10-12 weeks.