Why was it longer than they expected before they were ready to go to sea?

From the text:

"IT was longer than the squire imagined ere we were ready for the sea, and none of our first plans--not even Dr. Livesey's, of keeping me beside him--could be carried out as we intended. The doctor had to go to London for a physician to take charge of his practice; the squire was hard at work at Bristol; and I lived on at the hall under the charge of old Redruth, the gamekeeper, almost a prisoner, but full of sea-dreams and the most charming anticipations of strange islands and adventures."