Why Elasticsearch autocomplete suggestions' score is always 1

Question

I was reading https://www.elastic.co/blog/you-complete-me and I cannot find an explanation for one section about score:

Note: If you don't specify a weight then Elasticsearch will use the term frequency of the search phrase within its segment, usually 1. This is pretty much meaningless as far as suggestions go. It is better to control order using weight.

Why is the score 1 all the time for all suggestions?

Also, I tried running https://github.com/elastic/elasticsearch-dsl-py/blob/master/examples/completion.py but if I remove the "weight" it'll return 1 instead for the score.

I want it to return score based on relevance and term frequency.