Model rights has 2 levels, the allowed or set level (model rights level) and the meta level. If a model right is set to read/write but the meta level is set to read only the action will still show up as green in the list. When synchronizing the model rights to IAM the model rights will be adjusted to fit the meta level setting. So when applied to IAM the action will be shown as yellow (read only), even though it shows as green in model rights in the SF.
To make this process more user friendly I suggest instead of showing the model rights level show the lowest level instead (since this is the level that will be applied to the IAM database).
Unfortunately, this idea has not received enough votes. Because we want to keep the focus on ideas that are in high demand in our Community, we are closing this idea.