I am not a fan of having to do things over so I started to miscount my starting chains deliberately. If a pattern called for 180 chains I made about 185. If the pattern said to chain 25 inches I chained 26 inches. I always make sure I have a chain that is too long for my project.
Therefore when I get my first row completed I always have a length of starting chain left over.
To remedy this I leave a tail about 1 to 2 inches long attached, then I cut the rest of the chain off and carefully unravel the remaining stitches back to the edge of my item being very careful not to get into the working stitches. From here I then work in the loose end. Yes this does waste a bit of yarn however I find the peace of mind is well worth the waste.