Fragile question

Am I the only one who was bothered by an inconsistency in Lisa Unger's book, Fragile? On page 234, "Maggie watched Henry exit his front door and lock it behind him. She wondered how many times she's watched him do that over the years of their friendship." Then just 50 pages later on page 286, "Henry Ivy rarely lock his doors." Whether this was a case of slopping writing or editing, it spoiled the whole book for me. I'm not likely to read anything else by this author.