Per documentation:
https://doc.arcgis.com/en/survey123/desktop/create-surveys/quickreferencecreatesurveys.htm#ESRI_SECT...
Question names and choice names should not contain special characters, such as spaces, commas, hyphens, parentheses, brackets, or characters such as $, %, and #. It is important that choice names for select_multiple questions do not contain spaces or commas.
The 'question names' in the survey sheet provide a warning if a special character is used in the name column.
The 'choice names' don't provide any such warning and it's extremely common for spaces and other special characters to be used in this list. This causes issues down the track when working within the XLSForm or when working with domain values, such as in ArcGIS Pro.
From my experience working with a lot of users, this documented requirement is not well known and frequently missed in survey design. The issues manifest later when it is too late.
Having a simple data check like the green triangle will help users understand that there may be implications of having special characters in the choices name column.
