If Ash was unable to complete the kill after establishing the connection using her technique then she would not gain anything from all of the efforts put in.
The first rule looked out for her morale compass,
the second rule was to be certain that she was picking the correct target and would not make any rookie mistakes that she would come to regret later.
The third rule made it so that when she did act, those targeted would not be too close to her and the act itself would not be too personal for her that it could cause issues later.
The third rule helped to make it so that she could not be identified as a potential culprit too which was just as important.
The fourth rule made it so that Ash would approach each case carefully and plan ahead of time to help better protect herself from leaving behind any room for failure.
The next rule was rule five which would be just as important.