LOS ANGELES—Acknowledging his recent output had failed to live up to its full potential, Hollywood director Tim Burton expressed concern Monday that he might be going through a bit of a 14-movie slump. “It just seems like I’ve sort of been in a rough spot here for the past two or three decades,” said Burton, 59, admitting that he really thought he had turned a corner with Big Fish, only to take eight steps backward with Charlie And The Chocolate Factory, Corpse Bride, Sweeney Todd, Alice In Wonderland, Dark Shadows, Frankenweenie, Big Eyes, and Miss Peregrine’s Home For Peculiar Children. “I recognize, of course, that it’s all part of the process. Sometimes, you just need to make 14 bad movies to make a good one. Still, it’s not fun knowing that your artistic impulses haven’t been totally aligning for the last three quarters of your career.” At press time, Burton vowed that he would plow through his next six bombs as quickly as possible so he could put everything he had into Beetlejuice 2.