1.When the cost by LCL is more than by FCL 2.When the time is very tight ,arranging FCL can meet the schedule but LCL can't. 3.As you know, there are road limited weight in U.S.A. Even if the container is not full but the weight is over the limited weight.You have to ship it as FCL.
But the shipper should advise cnee when the estimated volume is less than container as the cnee maybe have other venor 's cargo to combine.
Replying to [Foow]: Some of our customer they would like to doing like this. just ship the goods in a FCL container but the CBM just half of the container. they said the ocean freight cost and their local charges price are lower than LCL for the goods sometimes. It depends on your time and cost I think.