There are all kinds of wonderful resources out there that can help you become a better photographer. For sports photography they always tell you to find a good spot on the sideline and use a tripod. When the sports figure goes flying by you can take great action shots with your telephoto lens.
With wildlife photography they tell you to pack a lunch, take your time, sneak up as close as you can get to your subject, set up your tripod and use a huge honking telephoto lens to reach close enough to to snap a photo without spooking the animal.
These skills I had practiced. These skills I had developed. These skills I could almost say I had mastered. But let me tell you, when you're trying to take pictures of Shetland sheep you can flush all those skills right down the toilet. None of it matters.
Nope. No one will tell you that the sheep will belch in your ear while your setting up your shot. Nor will they remind you that you'll need a damp cloth to clean your lens after the sheep lick it. They don't tell you how to prevent them from chewing on your camera strap. They fail to mention that you will need running shoes instead of a tripod.
And you'd better be in good shape. Because you'll need to run ahead, turn, squat and hope to snap a few shots...before they catch up with you.
Where they will belch in your ear, lick your camera lens and eat the strap until you take off running again...