update statistics not occur

[bibi92]

For information after deploy the new script IndexOptimize, we see that update statistics not occur with these parameters :

@UpdateStatistics nvarchar(max) = 'ALL',

@OnlyModifiedStatistics nvarchar(max) = 'N',

@StatisticsModificationLevel int = NULL,

@StatisticsSample int = '100',

@StatisticsResample nvarchar(max) = '100',

How is it possible to explain that ?

Thank you

Best regards