This was actually intentional as it looks better:

Karl@h3002993:~$ perl -E 'map {say 1..10} 1..5'
12345678910
12345678910
12345678910
12345678910
12345678910
[download]

Or:

karl@h3002993:~$ perl -E 'map {say join " ", 1..10} 1..5'
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
[download]

Compared to:

karl@h3002993:~$ perl -E 'map {say for 1..10} 1..5'
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
[download]

Update: Probably I meant  perl -E 'map {print for 1..10,"\n"} 1..5'

This was actually intentional as it looks better

But the whole question is about nested loops. By changing the code to look different, you completely missed the point.