What's the difference and why would it be important?
I mean, the man was on a sinking ship, surrounded by other men on a sinking ship, and they were all trying to float the lifeboat. Would it have made him less of a man than the men next to him who were only trying to save his own life? And, let's say that Lightoller was doing it 60% to save himself and 40% to save others, how would you measure that?
From Lightoller's testimony, which of course is suspect if you're evaluating the man's motives, the ship left him. He actually went down on the Titanic. He didn't get to the lifeboat until after he came back up. This would imply that he was freeing the lifeboat solely for other people, and didn't get on it until after the ship sank and he happened to be floating next to a perfectly good lifeboat in the middle of the North Atlantic.
On the other hand, the infamous overturned lifeboat also reputedly left stragglers in the water. Since Lightoller was the ranking man on this boat, he was responsible for all persons turned away and left to freeze. This could be judged as an entirely selfish motive on his part, or as a command decision to save the lives of the others on the lifeboat.
In general, given the man, his testimony, and what little rumors I've heard of his history he seems to me to be a very by-the-book kind of guy. The kind of man who possibly would have floated the lifeboat entirely because it was his by-the-book duty, regardless of how many lives it saved.
