The LOOK algorithm (wiki) is the same as the SCAN algorithm in that it also honors requests on both sweep direction of the disk head, however, this algorithm "Looks" ahead to see if there are any requests pending in the direction of head movement. If no requests are pending in the direction of head movement, then the disk head traversal will be reversed to the opposite direction and requests on the other direction can be served.
In wiki there is a line which says
LOOK behaves almost identically to Shortest seek time first (SSTF), but avoids the starvation problem of SSTF.
Is it(LOOK) always successful in avoiding starvation or there might be some order of disk request where it may lead to starvation.