AN JOSE — As their latest patent trial drew to a close Tuesday, lawyers for Apple and Samsung took a stab at answering a question that is top of mind for observers: Why are they still going at it?

Delivering Apple Inc.’s closing argument, Morrison & Foerster partner Harold McElhinny stressed that Samsung reaps a handsome profit from sales of infringing phones. A modest damages award would do nothing to deter the infringement, he said.