Have you ever been in that situation?For the same pixel of sentinel-3 OLCI level-2 products, OGVI has value but OTCI was in no data. As shown in the figure, the original level 2 product just downloaded and has not been preprocessed such as reprojection and resampling.
It could happen that OTCI and OGVI have different thresholds for considering valid pixels. I advise to look at the ATDB for clarification.
Thank you!