A retail company recently migrated to a data lake design based on Amazon S3. Amazon Redshift and Amazon QuickSight are being used by the company's data engineering team to analyze data for better insights. To ensure access to the most up-to-date actionable data, the team has now shifted to a nightly Amazon Redshift refresh utilizing terabytes of the previous day's changes. The team has noticed that post the switchover to nightly refresh, several popular dashboards that had good performance earlier, are now seeing degraded performance during business hours as well. Amazon CloudWatch shows no notifications regarding the performance metrics. Which of the following represents the MOST LIKELY cause for this issue?