I found a number of quotes from a popular writer and favourite of Julius Caesar :- Publilius Syrus
Here are some of his maxims:
On agility in planning:
“It is a bad plan that cannot be altered.”
“Never promise more than you can perform. “
“Nothing can be done at once hastily and prudently“
“To do two things at once is to do neither “
2000 years later and the old Maxims are still relevant.