Why did Yaakov finally remind Lavan how he had switched the wages ten times?
Ramban (to 31:36): Refer to 31:36:1:1*.
Seforno: He was telling Lavan that, it was not he (Yaakov) who had stolen from him (Lavan), as Lavan had claimed (see 31:26,30), but rather Lavan who had cheated him. 1
Ha'amek Davar: Because you are a swindler, you suspect others (i.e. me). One who has a blemish, he accuses others of having that blemish! (Kidushin 70b)
Why did Yaakov see fit to state here, "Zeh Li Esrim Shanah be'Veisecha...;" he had already said "Zeh Esrim Shanah Anochi Imach... " (31:38)?
Oznayim la'Torah: Based on the Seforno's explanation to 31:24 (Refer to 31:24:2:2), he was telling Lavan that, bearing in mind his dedication during the fourteen years that he worked for him (see 31:39-40), Lavan had no reason to do him harm; and bearing in mind that he had worked for fourteen years (seven of them under false pretenses) and then six years during which time he (Lavan) had changed the conditions ten times, why on earth should he (Yaakov) wish to return to him?
