Specifying inclusion masks in tckgen vs using tckedit on .tck file

tckgen FOD_WM.mif output.tck -seed_image seed_mask.mif -include target_mask.mif -select 0
-seeds 10000

versus

tckgen FOD_WM.mif output.tck -seed_image seed_mask.mif -seeds 10000 -select 0
tckedit output.tck -include target_mask.mif -out output.tck

What is the difference between these two methods for generating tracts between a seed image and target ROI? If I run both, I end up getting a similar number of streamlines (but not exactly the same) when I keep the rest of the parameters constant.