s actions prevail over the original draftor of the contribution is that s/he HAPPENS TO ARRIVE LATER. 
 The original draftor isn't told that his contribution was altered, or that he wasted their time. If he wants to know the fate of the material he painstakingly added, he has to check back. 

 One arrives at Wikipedia with great aspirations, thinking it is a good thing. 
 But quickly, the person becomes disillusioned.  
 What s/he thought were worthwhile contributions are thrown in the bin without explanation or discussion.  
 When one checks to see who has done it, one gets the impression that it has often been done by people who have been here longer, possibly part of an inner circle who think they know best. Longevity on an internet site tends to breed arrogance, particularly as regards one'e attitude to a newcomer. 

 So this note is an aide memoire to myself, not to change any page, ever again. The effort isn't worth it. Wikipedia will probably get there in the end, but in the meantime it breeds anger, frustration, annoyance, wastes people's time and labour and leaves individuals very confused when they are treated like rubbish.