If you have a big enough yard, yard work in itself is a constant stream of work even if you have all the right equipment
It hadn't been done for about 5 years when we moved in, so one of the neighbors spent 200 hours cleaning it up for us. Not joking, 200 hours of labor. Scotch Broom is a literal nightmare.
Soil erosion.
My last house didn't have anywhere near as much land, but there was a fairly steep hill on the back of the house. We ended up having part of the slope dug out and a "seat-height" retaining wall installed, with drainage installed as part of the build, and lots of low-maintenance plantings. Reduced the work from weekly mowing on a slope to occasional weeding and trimming. But, it wasn't cheap to do properly.