I always think this about garlic, chilli, onion, etc. Feeling all tough, naturally designed to punish whatever's just eaten it. Then humans be like, "OOOOO that's yum. Add a bit more."
We like plants that offer a challenge, apparently. We probably evolved to like these chemicals because we refused to be beaten and just ended up liking them.
Things like onions, garlic, chili and spices have anti microbial properties. This is why warmer countries tends to have spicier food, it protect from food poisoning.
Passing through the digestive tract of a mobile animal is a good way for plants to disperse seeds and reproduce. It makes sense that some plants would be naturally repulsive to some animals and attractive to others.
Also the plants and the animals evolved together. If you're the only animal in the desert that can chomp on a cactus, you're going to survive and pass on your genes.
We don't know whether they evolved these chemicals to prevent being eaten by animals though. People have tested spicy (capsaicin based) foods with mice, and found that mice actually seemed to like or not really react to spicy foods. This means that capsaicin did not evolve to protect against rodents like initially thought.
In fact, we now know that capsaicin is a very powerful antifungal chemical. Chili peppers naturally grow in hot, humid environments where fungi thrive. There also aren't many rodents in those areas. So the spiciness experienced by mammals like humans is just a side effect that didn't really affect its evolution.
I've never used or even seen this exact bar of soap until I just happened to buy it a couple days ago but haven't used it yet. Weird to see it here today but now I'm not sure if this means it's going to be good or bad on my balls...
You should definitely not test it by rubbing the bar of soap directly against them in such a way as to create a highly concentrated version of it directly on your balls.
I got menthol exfoliating soap gifted to me for christmas one year. I still have them in storage... because the feeling is so intense I only want to use it a few times a year, usually in summer. I mean this experience is so much sensation its like, holiday levels of memorable for me.
Well if you think about it, since we farm the plants the plants win at the end of the day. Their offspring are more in number even safer in farms compared to wildlife.