The two descriptions are completely distinct from one another and I can't think of a single word that describes both. For the first one, I would suggest:
slow to understand, think, or learn; stupid: the slow-witted interviewer
failed to pounce on his remarks.
Or simply slow. As in he's a bit slow.
And for the second one, I would suggest:
not motivated or driven by a strong desire or determination to succeed.
• (of a plan or piece of work) not involving anything new, exciting, or demanding.
Definition source: NOAD