Bed Bath & Beyond on Tuesday posted wider quarterly losses than expected as its chief executive acknowledged the struggling retailer’s turnaround plan had not achieved its goals. Days after the company warned of potential bankruptcy, it painted an even more dire picture of its finances. Bed Bath lost $393 million during the fiscal third quarter, it said Tuesday, worse even than the $385.8 million quarterly loss it projected just last week and a 42% increase from year-ago losses. Bed Bath’s net losses have now exceeded $1.12 billion for the first nine months of the fiscal year.