Maybe because :If Pep is right and we cannot afford Haaland and one would assume therefore Mbappe or Kane, then I cannot understand why we have not just renewed Agueros contract for another season. An easy option especially in this current econmic climate. The man is now getting back to fitness will guarantee goals. We will not get by without a No.9 forever. I hope Pep is wrong otherwise I feel we're being short-sighted IMO.
City including Pep and Board feel that Aguero has a poor injury record
His salary
Characteristics Pep needs in a striker
Maybe Aguero didn't want to extend with a lesser salary, he feels he can sign more than a 1 year extension or having a new challenge to motivate himself for the last years of his career, he is not old 32 is noghing when you have a good fitness.
Maybe City want to free some wages in order to sign another player
Like every team City is also concerned by the pandemic the revenues will be lesser it doesn't rain money