Continuity mistake: When Annie grabs Ash while he is lying on the floor you see lots of blood getting all over Annie's right shirt sleeve. Later on her shirt is totally clean. (00:36:20 - 00:37:30)
Continuity mistake: When Ash is thrown into the cellar he breaks a few of the steps. Later when he goes in to retrieve the pages of the Necronomicon every step is intact. (00:38:30 - 01:08:10)
Continuity mistake: After Ash hacks Evil Ed up, a lot of the green blood which sprays all over the walls disappears. (00:43:40)
Continuity mistake: When Ash hacks Evil Ed, the clock reads 11:10. Later when the clock is shown stopping, it is 10:40. (00:43:40 - 00:45:00)
Continuity mistake: When the hillbilly is killed by Henrietta, blood is spraying everywhere, and Annie is totally drenched by it, but in the next shot, she is totally clean except for the one blood stain mentioned on this mistake page. (01:03:30)
Continuity mistake: After the hillbilly is killed by the Henrietta deadite Annie has a blood stain on her left shoulder. Then she runs into Evil Ash and it has switched to her right shoulder. (01:03:40)
Continuity mistake: When Ash is crawling through the cellar, he finds some of the pages, and he holds them in his right hand. Only problem is, he cut off his right hand earlier and attached the chainsaw to it - the film was flipped so he'd appear to be crawling in the right direction. (01:06:15)
Continuity mistake: When Henrietta is attacking Ash, the clock in the background alternates from reading 1:15 or 1:30. (01:09:00)
Continuity mistake: In one scene, Ash finds some pages from the Necronomicon lying in a mud puddle. He picks up the pages, and they're dry. (01:10:00)
Continuity mistake: When the evil force is speeding towards the cabin door, when the trees are attacking the cabin, the shotgun holes in the door are missing. During alot of the film the holes change size/shape too. (01:12:30)
Continuity mistake: During the movie, you can see that the metal handle of the chainsaw switches between being thin and thick. This is because they had replaced the handle half way through the shoot and had just painted the regular one silver and brown.
Answer: Sam Rami could not get the footage of Evil Dead to use in the sequel, so he remade the movie in a shortened form for the beginning. Since Linda was the only original character other than Ash to come back he included her in the recap but deleted the others as not to waste time. An in universe answer could be that trauma of losing his friends made Ash block them out and rewrite history in his head, except for Linda who comes back to haunt him in the movie so he is forced to deal with it.