Spurs were open to offloading others, such as Toby Alderweireld and Danny Rose, with Pochettino not keen on having unsettled players on the fringes of his squad who could potentially be disruptions as the season goes on.
Pochettino praised the work being done on the club's new ground and the training complex and in securing top players like England duo Harry Kane and Dele Alli on long contracts.
Spurs were the only Premier League club not to make a summer signing after their move for Jack Grealish collapsed but Pochettino said: "What the club is doing is showing it is so courageous". I think the club is doing an unbelievable effort to try to finish the stadium as soon as possible, and the lodge is finished at the training ground.
"Building a stadium that is almost £1 billion".
"With Brexit it is worse because the cost is 30 percent more - that is a drama, I feel sorry for the English people - and then keeping the best players, for me [that] is to be courageous".
West Brom in competition with West Ham to sign Fiorentina midfielder
Financial details of the deal were not disclosed, but local media said West Ham had paid about 4 million pounds for the Spaniard. However, the striker then opted to return to Deportivo on loan last season in search of more regular first-team football .
Asked if Tottenham's players understand the lack of new arrivals, Pochettino responded: "They don't need to understand".
"Of course it's hard to understand for people in football that Tottenham didn't sign or sell players, but sometimes in football you need to behave differently", he said. And if they don't play then I don't want them to give up and start to say: 'The gaffer is a bad guy.' It's not a drama - drama is another thing.
"For me they are part of the team".
The Scotland worldwide was a key man during a loan spell at Villa Park last season, but as the Villans hit financial difficulty early this summer, they were unable to put anything in place that allowed them to keep the playmaker.