1- I followed mma and a lot of people didn't believe in the hype behind Askren as he was coming into the UFC. He was hyped up from his Bellator and OneFC run but lots of fights he had a hard time getting his wrestling going and almost lost a lot of fights because he never had a set up for his grappling. It worked because he was fighting in places where the focus in training wasn't grappling or wrestling based. His wrestling credentials are legit, but you can't honestly think that being one dimensional will get you far in today's mma landscape. Every one has to adjust to all aspects of mma and be proficient enough in everything else. Even Khabib who's greatest strength is grappling worked on his stand up to the point he can stand and trade with elite strikers. Askren never worked on his striking and just wanted to rely on his wrestling. It's obvious in his fighting style and how he was training. Just look at the match ups he had in UFC, do those match ups favor Askren? He was brought in to lose to try and discredit OneFC.
2- OneFC at the time had a lot of fighters not really focused on the grappling aspect so it was a weakness early on for most of their fighters. It's different now but it's still lacking compared to areas that have western wrestling or dagastani wrestling etc, especially the ones that mix the wrestling with bjj.
3. If you follow peoples careers that come from other promotions that were popular or previous champions they are given hard fights to help prove the UFC brand is better. If they win their first fight they will lose their next and so on and then UFC will build them up. If they do happen to win their first fight usually it's very competitive and it could've gone either way. It's bad business to bring someone in from another promotion that's your competition and he just steam rolls through the UFC fighter. That's a bad look for the brand of UFC having the best fighters.