It was reported earlier in the week that Napoli and Maurizio Sarri would be meeting soon to discuss a long-term contract extension that would raise Sarri's wages and replace the option years on his current deal. Apparently, however, they decided to jump the gun a bit: reports in Italy indicate that Napoli have already triggered Sarri's option clause for this season, and did so before even sitting down to negotiations.
The one-year option being triggered that, as of now, Sarri will be making the same as he did last year, around €750,000 plus bonuses. That is well short of the three-year, €2 million per season deal Sarri was believed to be looking for, and between that and the lack of negotiations so far, it might not sit well at all with Sarri.
Hopefully this doesn't actually cause any tension between Napoli and their manager. With the original one year contract Sarri signed set to expire soon, this could simply be Napoli's way of making sure they keep hold of him while they negotiate something more permanent, and they communicated that reasoning with Sarri before executing the option.
But Aurelio De Laurentiis does what he wants and how he wants, so there's no way to know for sure that everything was as well thought through and executed as that. There is, unfortunately, every chance that this was done without consulting Sarri first, or even as a measure to take negotiating leverage away from the manager heading into their extension talks. That would be, at best, very unfortunate, and could cause a lot of trouble for Napoli this summer.
Fingers crossed that this all turns out for the best, but -- well, things don't always turn out for the best for Napoli.