In chapter 5 of A Wizard of Earthsea, what does the Pendor fisherman think Ged does not have?
Your question is not specific enough. Which fisherman in this chapter are you referring too? Also, there is nothing that any fisherman says to Ged that deals with a lack of something or someone. The main fisherman we are introduced to in this Chapter is Pechvarry, who becomes Ged's friend, so if you mean that Ged lacks friendship then this is what you want to focus on. However, when Ged telle the Head Isle-Man of his intention to fight the dragons, it is obvious that the Head Isle-Man is sceptical of Ged's ability to fight and win against nine dragons:
All that listened there thought this a folly or a crazy courage in their young wizard, and with sullen faces they saw him go, expecting no news of him again. Some hinted that he meant merely to sail back by Hosk to the Inmost Sea, leaving them in the lurch; others, among them Pechvarry, held that he had gone mad, and sought death.
Could this be what you are looking at? Here you can see the many doubts that the fishermen have of Ged and his decision to fight the dragons, though none specifically accuse him of lacking anything.