John Gill Commentary 1 Samuel 13:8

"And he tarried seven days, according to the set time that Samuel [had appointed]: but Samuel came not to Gilgal; and the people were scattered from him." — 1 Samuel 13:8 (ASV)

And he tarried seven days, according to the set time that
Samuel had appointed
He tarried to the seventh day, but not to the end of it, or towards the close of it, as he should have done:

but Samuel came not to Gilgal ;
so soon as Saul expected:

and the people were scattered from him ;
many deserted him, the Philistines drawing nigh, and Samuel not coming, as Saul expected, and had given the people reason to expect.