Affairs are easier of entrance than of exit; and it is but common prudence to see our way out before we venture in.
AesopA wild boar was sharpening his tusks upon the trunk of a tree in the forest when a fox came by and asked, Why are you doing that, pray? The huntsmen are not out today and there are no other dangers at hand that I can see. True, my friend, replied the Boar, but the instant my life is in danger, I shall need to use my tusks. There will be no time to sharpen them then.
Aesop