When changing a field type from Text to Number Integer, there is no warning of loss of data when some records contain fractional amounts. As the current records being viewed may not display this reality, it would be more considerate and familiar to the user to present the warning of what they are doing.
When I did make this change, I did notice that a better choice would be Number (Float) but changing to that option did not return the fractional amounts. I had to use the Undo but a warning at that moment would be a kinder choice.