The reason we aren't in the market yet is that we have a massive squad, expensively assembled, the majority whom (apart from players who have come from the academy teams) have been purchased in the last 2 years.
We don't need a massive transfer binge, we did that last summer:
Lloris (purchased 2012)
Vertonghen (purchased 2012)
Chiriches (purchased 2013)
Dembele (purchased 2012)
Capoue (purchased 2013)
Holtby (purchased 2013)
Paulinho (purchased 2013)
Sigurdsson (purchased 2012)
Chadli (purchased 2013)
Lamela (purchased 2013)
Soldado (purchased 2013)
Eriksen (purchased 2013)
In addition to the above, the following have only just made their breakthrough into the first team:
Kane, Townsend, Rose, Fryers, Veljkovic, Pritchard.
That leaves only Kaboul, Dawson, Assou-Ekotto, Freidel, Sandro, Lennon and Adebayor as longer-term members of the squad.
Pochettino's brief as per Levy's end of season letter is to get the best out of the players bought in last season's splurge and the previous summer. Some of the players like Lamela, Soldado, Capoue, Chadli, have hardly had a chance to show what they can really do yet with a settled system and proper coaching.
I actually saw what Paulinho could do in Brazil's last match, much better from him.
Pochettino will be assessing the squad in training and maybe even the first few friendlies. If there is a position then that he thinks he won't be able to use any of the existing players in then we'll move then.