Under the global EV budget, you can max out 2 stats but then only have spares to earn a single stat point in one other stat. If you indeed have those two stats all the way at max, but then have spares in all four others, then they have to be so insignificant (1-2 EVs each) that you don't even get the last stat point.
When you have a Pokemon like Weavile, attack and speed are the most important assets for it, so maxing those out first is almost always a more meaningful impact than putting any focus into any other stat, diluting the budget more than 2 ways.