Whenever you write a world football article about "the greatest ever," you're on a hiding to nothing despite Pele, Maradona and probably Messi and Ronaldo being on everybody's list.
When it comes down to "the greatest No. 10s," there's an even bigger problem. You see, apart from the fact that some No. 10s didn't even wear that number, there is the whole thing about Trequartistas.
Then, if you're not careful, you get sucked into the debate between Trequartistas and Registas. And why is that relevant, you might say?
Well, the thing is that Paul Scholes started his career as a No. 10 and now plays Regista, as does Carrick, Del Piero, even Xabi Alonso and Xavi.
The game has changed. Some of the old Trequartistas have become Registas because that is the way their team plays, and some because they don't have the legs anymore.
Alessandro Del Piero would have made a great No. 10 in the days of Baggio, and he showed that he can have as much effect on the game now in the way he dominated in the Euros from a deeper position.
Similarly, the Manchester United fans who constantly carp at Michael Carrick simply don't understand that he is under instructions from Sir Alex Ferguson to play as a Regista. As Ray Wilkins said in summarising his performance against Newcastle, "he was absolutely outstanding."
But he won't be on our list.
And we're not talking about Trequartistas here, even though some of the names here have played that way and one of them invented it.
And no, the chosen few didn't necessarily even wear the number. But if you've been around football long enough, you'll recognise this chosen 10 as what they are or were.
Denis Law was a No. 10 and started his football in the times of 2-3-5, so he would originally have been called an "inside forward," as was Johnny Haynes, who also wore the shirt. But Jimmy Greaves was a No.10, as we would understand it, playing off Alan Gilzean wearing nine.
Now we're going to create a little twist here, because you've probably read articles like this before or had a heated discussion in a bar.
So, we shall only choose one from each country while mentioning some of the other greats in passing.
Before we start, who would be your 10 greatest on that basis?