Just an example: two days ago, I had to dismount the bicycle for a good km downhill, walking on the side for 1-2 km/h and trying to keep the balance. According to Komoot, some bold guys take it downhill, or maybe I misunderstood and got the wrong path, but the trail was narrow and covered with very sharp stones I would never ever do it.

Unfortunately the area is covered with recent lava flows...

Result: a couple of good, although old, Shimano shoes written off.

But really a wonderful ride, although technically above my level.

Taking another road on the way back home, all uphill, I was much, much faster... On the way back, I found a plaque at a scenic spot that expressed the situation well:

The plaque reads, "Rest break of the Plan of the Deads"...
Exactly how I felt at that moment!
p.s. this was actually "DOWN hilll the whole way!"