We were still in Europe when Suarez signed. Coutinho is young, his career still not established and Sturridge was getting a few minutes here and there for both Man City and Chelsea, career not really going anywhere. Not being in the CL and/or, in fact, Europe is a factor. Not the end all, be all for some players but still a factor. Especially when we can't offer huge wages either.I really think the 'we're not in the Champions League so we can't attract top players' line is a convenient excuse for us failing to land quality players.
We signed the likes of Suarez, Coutinho and Sturridge without CL football. Spurs signed Vertongen last summer without CL and Paulinho and Soldado this summer without it.