Problem with writing elements of an array using the pointer

The first loop is works perfect. Second doesn't works. What is wrong with 'Z'. Why the loop doesn't stop? When I will give 'Z' inside in table the loop doesn't react.

#include <iostream>
using namespace std;

int main()
{
    char tab[] { 'A', 'B', 'C', 'D', 'E', 'F', 'G',
                'H', 'I', 'J', 'K', 'L', 'M', 'N',
                'O', 'P', 'Q', 'R', 'S', 'T', 'U',
                'V', 'W', 'X', 'Y', 'Z' };

    char *wsk = tab;

    while(*wsk <= 'Y')
    {
        cout << *wsk << " ";
        wsk++;
    }
    cout << endl;

    wsk = tab;
    while(*wsk <= 'Z')
    {
        cout << *wsk << " ";
        wsk++;
    }
    cout << endl;
}