Review Search Terms Before Increasing or Decreasing Bids

Bid adjustments are often treated as the first response to weak PPC performance.
However, changing bids does not solve a traffic-quality problem.
Before increasing or reducing bids, the search-term report should be reviewed to understand what users actually typed before clicking.

I would separate the terms into four groups:
Relevant and converting
These terms may justify additional budget or more specific advertisements.
Relevant but not converting
The issue may be the landing page, offer, price, or insufficient data rather than the keyword itself.
Informational
These searches may be related to the topic but not indicate immediate purchase intent.
Irrelevant
These should normally be excluded with appropriate negative keywords.
This process can also reveal missing campaigns. A broad keyword may unexpectedly attract a valuable subtopic that deserves its own advertisement and landing page.
Bid changes affect how much traffic costs and how often the advertisement appears. Search-term analysis determines whether that traffic should have been purchased in the first place.
Optimizing price before checking relevance can make an inefficient campaign cheaper without making it profitable.

Totally agree. Looking at search terms first usually tells you why performance is down better than messing with bids right away.