Why does the processing time of the blob tool fluctuate?
As the number of blobs increased the time will increase. If there are a lot of small blobs the blob tool will take a lot of time. This is because of all the information that is associated with each blob. If you want to save time, shut off the “output blob list” display in the properties of the blob tool. This will still run blob but not generate the display for them. If you still need to see the blobs then you will have to expect the long run time.