What is an advantage of first-fit in heap management?

Another advantage to the first-fit algorithm is that it tends to suffer less from a degenerate condition known as external fragmentation. Fragmentation occurs after a long sequence of allocation and deallocation requests. Remember, when the heap manager satisfies a memory allocation request, it usually creates two blocks of memory — one in-use block for the request and one free block that contains the remaining bytes in the original block after the request is filled (assuming the heap manager did not find an exact fit). After operating for a while, the best-fit algorithm may wind up producing lots of smaller, leftover blocks of memory that are too small to satisfy an average memory request (because the best-fit algorithm also produces the smallest leftover blocks as a result of its behavior).