Most of the time in SQL, you can simply join tables or views to one another to get the result you want. Often you add inline views and scalar subqueries to the mix, and you can soon create relatively complex solutions to many problems. With analytic functions, you really start to rock ‘n’ roll and can solve almost anything.
But it can happen from time to time that you have, for instance, a scalar subquery and wish that it could return multiple columns instead of just a single column. You can make workarounds with object types or string concatenation, but it’s never really elegant ...
