User blog comment:GinIchimaru/Gin in context./@comment-1906999-20100901195828

I still think that Ichigo will play some part in Aizen's plan somehow, because Aizen said he was waiting for him to come get him in RKT and seemed mad at Gin when he fought Ichigo, so so i think the fight could of had a real purpose. It could be that he knew he wasn't strong enough to defeat Aizen if Gin couldn't, so he taunted him and gave him negative reinforcement in order for him to want to get stronger. Very few things make someone want to do something more than being told they can't do it, so gin telling Ichigo he would just die and telling him to run away could be a reverse psychology type of thing. The only problem with this theory is that he had no idea that Ichigo would actually get the chance to train in the Dangai, since he couldn't have known Aizen would destroy the Kototsu and even tried to make them leave the Dangai.

My other theory is that Gin truly wanted him to run. If Ichigo does have some role in Aizen's plan, if Gin could convince him to just give up and run away, Aizen wouldn't be able to use him for whatever purpose.