A question about off-site reclamation???

I have my scheduled reclamation set by the reclaim=80.

*The process cycles thru and initially I have 29 volumes to be eligible
for reclamation based on the ANR1040I message at 06:25.

*Next, it cycles thru and 15 volumes are eligible @ 07:27.

*Then, 12 volumes @ 08:16

*8 volumes @ 09:02

*4 volumes @ 11:25

*Eventually, all the reclamation is finished.

Question is: since reclamation is driven by a threshold and since these
are off-site volumes and therefore are "regenerated", why does ADSM have
to recycle thru so many times (and therefore take so long) to complete
all of these volumes????????