Pretty sure they are the main reasons behind this move. Milner will start to slow down and therefore I can see him playing mainly in midfield rather than at fullback.On the one hand signing a player to be a backup is a pretty boring move, on the other it’s nice to have the biggest hole in the first team squad filled. Especially as Milner looks a little less capable to fill in at LB each year and Neco really needs to be able to focus on his primary position at this stage of his career.
Having said that if we sign Thiago he will struggle to get into midfield. Great pro to have around the team though , I can definitely see him leaving after this season.