Exercise 2: Why the Walkthrough Goes Alertmanager → Grafana → Loki → Jaeger — Possible Solution
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Explanation:

This order follows exactly what an investigator would actually KNOW
at each step, moving from the least specific signal to the most
specific one -- it isn't arbitrary.

1. Alertmanager is the entry point because it's the only piece in this
   whole stack that proactively tells a human something is wrong,
   without anyone needing to go looking first. At this point, all that
   is known is "checkout-service's error rate is elevated" -- nothing
   about WHY yet.

2. Grafana comes next because the dashboard's own $service-filtered
   view narrows "something is wrong with checkout-service" down to a
   specific TIME WINDOW -- exactly the aggregated-trend information
   obs1-1's own chapter names metrics as being good for. This step
   answers "when did this start," which is needed before searching logs
   usefully.

3. Loki comes after Grafana specifically because a log search is most
   useful once it can be narrowed to a specific time window and
   service -- searching Loki with no time boundary at all across a
   busy service's full log volume would be far less targeted. The log
   line found here supplies the one piece of information neither
   metrics nor a vague time window could provide: a specific trace_id
   connecting this investigation to one exact failing request.

4. Jaeger comes last because it needs that trace_id to do its own
   job -- without it, there would be no single trace to pull up out of
   potentially thousands of concurrent requests. Once the trace_id is
   in hand, Jaeger delivers the single most precise answer in the whole
   sequence: exactly which span, in which service, the time actually
   went to.

-- Why not start with Jaeger directly? --
--
-- Jumping straight to Jaeger with no prior information would mean
-- searching for "a slow trace" with no starting point -- no known time
-- window, no known trace ID, no known specific request to look for.
-- Each earlier step in the sequence supplies exactly the piece of
-- information the next tool needs to be used precisely rather than
-- as an unfocused search across everything.

WHY THIS WORKS AS AN ANSWER
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This explains the ordering by tracing what specific new information
each tool supplies to the next step, rather than simply restating the
sequence, and directly answers why skipping ahead to Jaeger would
leave the investigator with no way to narrow down which trace to look
at.