Los Che reached the semi-finals of the Europa League, but were eliminated on away goals by Sevilla.
In La Liga, meanwhile, the former Spanish champions finished in eighth position, 21 points off a Champions League position.
"The season hasn't turned out as well as we'd all wanted. I think it's been a very different season compared to others, mainly because of what's been going on around the club and the indecision about who was going to be the new owner," he told VCF Play.
"Out on the pitch, I also don't think we've found a way to improve enough throughout the season. There have been times we were good, others we were bad and in such a difficult season in La Liga, if you're inconsistent, doing good and bad, then you don't reach your objectives.
"We were enthusiastic about the Europa League, with the aim of getting to the final, to celebrate reaching a final and to win a trophy, but we didn't achieve that and for that reason, I can't see the balance of the season as being positive."