My friend Rox has a theory. We'll call it the "monkey theory".
She can remember the first time she ever saw a monkey when she was travelling. It was in Nepal, and it was a pretty exciting moment – monkeys are, after all, awesome. So she had her camera out and was chasing that thing around trying to get the perfect monkey shot.
It's a monkey!
Next time she saw one of our primate friends, in Laos, it wasn't quite as cool, but it was still worth trying to get a photo. And maybe chasing it. After all, you don't see a monkey every day, do you?
Now, however, things have changed. After spending plenty of time in South-East Asia Rox has seen about a million monkeys, and they're just not that exciting anymore. She doesn't want to take a photo of one. She doesn't want to try to pick it up. It's just a bit... meh.
(Anyone who's been on an African safari could probably relate. Remember zebras? First time you see a zebra it's pretty much the most exciting thing in the world. After a couple of days of endless herds of stripy horses, however, they're just boring. You won't get out of bed for anything less than Big Five.)
Rox's "monkey theory", of course, is not really about monkeys at all, but about how things you once found exciting can lose their lustre after repeated experience. That can go for a lot of things, but her main worry is that it will apply to travel in general.
Remember your first trip overseas? You would have been excited, and maybe a little bit scared, definitely keyed up and on edge. And it would have been an incredible trip. The world was bright and fresh – every experience was a new one, from the weird meal to the dodgy accommodation to the shonky lady who talked you into the henna tattoo.
There was no such thing as too touristy. Everything was amazing and different. It was an eye-opener. It was life-changing.
And it's impossible to sustain that feeling. Travel will inevitably lose its sheen of the new and exciting when you've already been to three countries, or five, or 20, or 200. The experience will shed some of the vibrancy that it once had.
The question is though, how much? Would you end up standing in front of a beautiful mosque in Esfahan and just shrugging your shoulders? Would you find yourself eating an amazing meal in some back alley in Barcelona and wondering what was on TV at home?
Is it possible to travel so much that, like the monkeys in South-East Asia, the whole thing just becomes a bit "meh"?
Never. Well, not for me, anyway. Travel will always be exhilarating – although there are some things that don't excite me as much as they used to. (And voicing these things unfortunately marks you out as an incredible travel wanker.)
I've spent the last few weeks in Morocco, a country I'd never previously visited. Arriving that first day in Marrakech, I was feeling just as excited and keyed up as I would have been on my first solo trip overseas some 15 years ago. Just walking the streets was a thrill.
New countries and cities still have the buzz of the unknown, and no amount of previous travel will dull that.
A few days later, however, things changed. I joined up with an Intrepid tour group and headed east into the Atlas Mountains. Most people in our little van were stunned at the scenery. "Look at that," one passenger said, his nose pressed to the glass, staring out at the barren valleys and rocky peaks around us, "it's incredible."
I smiled and agreed. "Beautiful," I said.
But that's not what I was really thinking. What I was really thinking was something like, "Yeah, it's OK – but it's got nothing on Switzerland. You should see the mountains there."
I didn't say that for the above-mentioned reason, but I still thought it. Because unfortunately when you've travelled a lot you're not going to be quite as blown away by things as you once were. You just have more to compare it to.
But that's not a huge problem. Because even when the thrill of travel is tempered slightly by experience, it's still exciting, like those first days in Marrakech. It's still one of life's great experiences. That won't change for me.
And for the record, I still think monkeys are awesome.
Do you think travel could ever be a bit "meh"? Are there things you used to get excited about that don't interest you anymore? Do you agree with the "monkey theory"?