When the players leave Winterhaven, they're set upon by a kobold ambush. Yes, again.
Mearls and Cordell must have really liked the idea of a kobold ambush, because not only is it the first encounter in the book, it's also the second. On its sophomore outing the ambush has most of the minions replaced by a single spellcaster, but it's otherwise the same battle. It even uses the same battle map.
It would probably be a bit baffling for players who are entirely new to D&D. They may end up describing it to their friends as "that game where you get ambushed by lizards".
The repetition might have been a deliberate design decision. There is something to be said for letting people try the same thing twice, to make sure they have learned how to do it before moving on to more complex scenarios. Learning by repetition works best, though, when applied to small, short tasks, rather than forty minute combat slugfests.
This happens a lot in Keep on the Shadowfell. Later, a memorable encounter with an ochre jelly (a kind of dangerous ooze) is followed by an encounter with a blue slime (a kind of dangerous ooze). Putting two of these rare monsters back to back cheapens them both. Similarly, a horde of mindless zombies in a graveyard is followed by a horde of mindless zombies in a dungeon, a tribe of goblin mercenaries is followed by a tribe of hobgoblin mercenaries, and a climactic battle against cultists and high-level undead comes just before another climactic battle against cultists and high-level undead.
Nothing ruins a satisfying encounter like an immediate rematch.