Man Utd has had terrible transfer policies since 2008. As much as I like Fergie, the last couple of transfer windows were awful. We sold Ronaldo and Tevez in 2009 and we never got the proper replacements for them. We bought the washed Owen and Antonio Valencia. We also bought the likes of Obertan, Bebe, Smalling and Cleverly.
In 2012, we were supposed to get Lewandowski and Evra said that Sir Alex planned to get Ronaldo and Bale as well. All of these transfers failed, and in 2013 our target was Fabregas and we had a panic buy of Fellaini instead. Aside from Bruno and RVP I can't think of any signing that has had a big impact on our team.
Every so called "rebuild" since 2006 has been bad and atrocious. Hopefully, Amorim will get the right players to fit his system and I hope he'll become a long term manager for us.