I have seen this problem many times over the years of using OneNote and believe it is caused by the Article clipping process starting before all the data is actually ready to be clipped. This results in the clipping being incomplete, missing the ending text of the clipping.
This problem was awful in previous builds but is much better now. I am not sure if it is because my Internet is faster or if OneNote has fixed the problem.
I use the following process with all the clipping I do:
After finding a Web page to clip and before clipping I always browse down to the bottom of the Web page. This assures that the full Web page has been loaded into my browser. I then execute the clipping and so far all of my clippings are complete without any missing data. Try it and see if it works for you.
PS. Article clipping does NOT work for all Web pages. It seems to ignore certain types of data or produces garbage text. If that happens select the text to be clipped and right click the selected data and select "Clip selection to OneNote" to paste to OneNote. You can also copy/paste desired data to an "untitled page".