You can't compete for all the trophies unless you are in the top 4, and you can't attract world class players unless you are competing for all the trophies. That's why, in my opinion, it's more important to get 4th place and an opportunity to play for every trophy than anything else, and then win a couple in the process.
What if you try and get fourth, miss out but win one cup and get to the final of the other. (Liverpool)
What if you invest all of your resources into league position, win nothing but come fourth - and still miss out in CL qualification. (Spurs)
It isn't a precise science. But some things help a lot. Spurs have had stability, trust and backing for their footballing management and consistant investment.
We have had two managers sacked, the DoF appointed and subsequently sacked for an unbelievable series of blunders. We have a recruitment process for MD resulting in hiring the marketing guy. We have sacked our Director of Communications just before the MD goes out and puts his feet in his mouth by saying we don't value the cups as much as the league position - despite him introducing an auto-cup money making scheme. (as someone on twitter said: a gerald ratner moment). We flip-flopped on the Suarez racism row and eventually threw Dalglish and Suarez under the bus.
That's why in my opinion it is more important to get the footballing and managerial structures in place, maybe win a trophy or two in the process before deciding whether we have been successful or not.