Why did the people complain to Samuel during his leadership?
The people complained to Samuel because his sons were ungodly and did not honor Jehovah. At the time of Samuel, Israel was doing fairly well, but Samuel's sons were a grief to him and were certainly not godly. When his ungodly sons began to carry on, the people began to complain that they were not honoring Jehovah.
Les explains that Samuel was the last of the judges. During the period of the judges, Israel repeatedly cycled: when a judge was on the scene, Israel came up spiritually and prospered materially, but when the judge died, they would forget Jehovah and dip into idolatry, leading to enemy oppression and servitude. At the time of Samuel, Israel had it fairly good, but Samuel's sons were a grief to him and were certainly not godly. When his ungodly sons began to carry on, the people complained to Samuel that his sons were not honoring Jehovah. This led them to the place in I Samuel chapter 8, verse 5.