we use umask 022 on linux profile when oracle database installation but why?

we use umask 022 but why?

The octal umasks are calculated via the bitwise AND of the unary complement of the argument using bitwise NOT. The octal notations are as follows:

• Octal value : Permission
• 0 : read, write and execute
• 1 : read and write
• 2 : read and execute
• 3 : read only
• 4 : write and execute
• 5 : write only
• 6 : execute only
• 7 : no permissions

so A umask of 022 allows only you to write data, but anyone can read and execute data.