What is the purpose of content previews?

An example of content previews is that you have a list of news articles all with different stories, in the list is the name of the article and then 2 lines of truncated content. An example can be seen on the LEFT side of the image below:

My context: We have a list of different reading material, right now we show the material title and the first 2 lines of material content. The user then has to tap on the content to open the full view. One stakeholder in my project thinks that we should save space and remove the 2 lines of content preview.

What is the purpose from a UX perspective does this content preview have and, to a further extent, what are the pros and cons of such a method?