Whilst this is true, you also have to account the fact that Poch came after Spurs got the Bale money and spent 110m pounds the year before.
During that Summer they got Eriksen (their second best player), Lamela - still playing for them. And during Poch they sold Capoue, Chadli, Chiriches, Soldado and Paulinho - recouping most of their money there.
You are comparing them with the nearest rivals, but since then Spurs won diddle squat compared to:
Man City - PL, 3 LC
Chelsea - 2 PL, 1 FA, 1 LC
Man Utd - 1 EL, 1 FA, 1 LC
Liverpool - CL final
Everton - Nothing
Arsenal - 2 FA cup
Spurs - 1 LC final
Leicester - with next to nothing indeed - 1 PL
In other words whilst being solid top four during his stint he also has nothing to show for in terms of trophies. All those teams that spend more than him actually won something and the only team that outspent him and did less was Everton.