I would have thought that this was a term used by people who were unrealistic in their expectations of babies....until I had one. Even before my daughter was born I knew we were in for a treat. The kid rarely stopped kicking. Once she was born, there was something different about her - and she was still kicking!
Part of figuring her out involved figuring out that she was really hard to burp. I knew something was wrong because I'd put her down to sleep and she'd wake up a couple hours later, obviously in pain. I couldn't figure it out because I'd feed and burp her beforehand. It didn't occur to me that there might by babies who are so hard to burp. The pediatrician told me she was just fussy. I knew that wasn't the answer. Finally, my mom came out to help, and figured it out. She also noticed that, in addition to having to spend a lot of extra time burping her, I'm too short to use my nursing pillow. Instead, she had to be fed sitting straight up. It's a little tricky to nurse her like that, but it has helped immensely. It also helped to keep her upright for a while after feeding her because she also has reflux. We are currently investigating the possibility of a food sensitivity. I suspect dairy upsets her, but we'll see. All of those things were discovered by painful trial and error - and through my mom's vast experience. The frustrating part was that I am NOT new to kids by any stretch, and even attended all the pre-baby classes. I called on my pediatrician for help, and not once did anyone mention the possibility of a kid being hard to burp or show you how to nurse a kid sitting up (although they have you practice all the other positions and make such a big deal about using your pillow in the "right" positions). Poor pumpkin! I feel bad that it took so long to figure those things out.
But wait! There's more! Figuring those problems out have helped some of her physical discomforts. However, there's also a personality component to her that is a little challenging. It's hard to explain, but she falls into the category of "high needs." She's super intense, is often hard to put down, doesn't enjoy cuddling, is not a great self-soother, is resistent to schedules and going to anyone else but mom, and is hyperactive in the sense that she is always tense and ready to go, and when she wants to kick - the speed and force is amazing. Really, in a nutshell, she's really hypersensitive. She startles easily, her moods change on a dime and if you don't respond to her she ramps up super fast. While I'm not complaining, I do admit to being slightly jealous when I see moms pushing their complacent kiddies in their stroller with such apparent freedom, or seeing young babies entertain themselves. My kid will do that, but only for short periods of time before she needs new stimuli. I would be concerned that somehow my behavior influences hers, but she genuinely gets angry at the little purple bear on her bouncy seat or the pineapple on her playmat. This is when I know it's time to take her out of the situation and soothe her a bit.
To be fair to her, she does try to communicate her needs - and I am getting better at understanding her. It just happens to be all about paying close attention to her and timing things just right so she doesn't have a melt down. She also has her "mellow" moments in which I can actually put her in the stroller and go out. And, she sometimes has good nights in which she sleeps for large chunks of time.
So, basically, I've spent my pregnancy learning about sleep training, the importance of schedules and lots of other goodies about parenting - most of which have gone (almost) out the window as I'm forcefully reminded that all kids are different and require parenting styles suited to their individuality.