SDT 5.1j

I thought there could be problems (corruption) with some of my tables. So I did a repair all

I noticed that some tables were repaired because of the informations displayed while that process was ongoing.

So after that I thought that repeating the same process would'nt display that some tables were repaired. But to my surprise the information displayed told that some tables were repaired

Is there something I don't understand here?

Unless 5.1j is too old and because my app uses VFP9 I should upgrade to the newest version of SDT?