Valverde is still battling doubters after last season's Champions League collapse against Liverpool.
But Abidal told Sport: "The more time that passes, the more decisions you have to take. There are players with talent, new signings, products from La Masia and we have to give them minutes.
"For the coach, it can be a risk, but it's part of the process and the management of the dressing room. There are players that can complain, but decisions have to be made."
Abidal continued: "I don't know because that's his decision. The only thing I know is that we spoke about the situation recently. He knows what happens day-to-day and keeps on with his work and we share information. He will decide when he has to decide. He will say, nothing else.
"I can assure that we've not spoken with anyone, although his future depends on results. You can see that (Valverde) likes coaching. At the end of the day, only he can say if he wants to continue based on how he feels."