In addition to getting out od the way I prefer when an ORM allows me to extend it to build my own abstractions. For example in Rails when I have a complicated

In addition to getting out od the way I prefer when an ORM allows me to extend it to build my own abstractions. For example in Rails when I have a complicated query, I can make write some SQL, stick it in a view, and make a view backed model. Then I can keep using Active Record to make it easier use the query in multiple places, easily compose additional queries etc...