Committing $10 an hour locks in $87,600 of spend for the year

Ten dollars an hour is the example rate in the dev.to write-up, and the discount applies to usage up to it ^[1]. Across a one-year term that rate is 8,760 hours and $87,600 of committed spend ^[3]. Hours when the fleet runs below the rate are what the post is describing when it says "Over-committing is worse than under-committing, because unused commitment is pure waste" ^[2].

Within the RI family the tradeoff is discount against flexibility. Standard RIs carry the biggest discount and the least flexibility, while convertible RIs take a smaller discount and can be exchanged for different families later ^[5]. The EC2 Instance Savings Plan sits between the two, committing to one family in one region for more discount than a Compute plan and more flexibility than a standard RI inside that family ^[8].

Family churn is the variable that decides it. The post's default for most teams is a Compute Savings Plan, trading a few points of discount for not being locked to a family you might migrate off ^[13]. Committing to a configuration has three justifications in the same post. An RI can reserve capacity, guaranteeing you can launch that instance in that AZ ^[6]. The bigger discount is worth the lost flexibility for a large, stable workload certain to stay on a specific family ^[14]. And RDS, ElastiCache, Redshift and OpenSearch have no Savings Plan option at all, so a database commitment is a reserved purchase or nothing ^[9].

The paralysis is the one part of the argument with no number attached. The post says teams freeze because there are two mechanisms, several flavors of each, and a real risk of locking in the wrong thing for a year ^[18]. The only figure on the other side is the discount band, often 30 to 70% ^[10]. That band covers both mechanisms and both term lengths ^[10], so for the top of it to describe your bill, the workload has to be the large stable single-family fleet the post reserves for standard RIs and EC2 Instance plans ^[14].

Then there is the tooling. Cost Explorer will generate Savings Plans and RI recommendations from your usage history ^[16], and that history predates the rightsizing the post puts first ^[11]. A recommender fed a year of oversized instances proposes a commitment sized to oversized instances. The post treats the output as a fine starting point and says to run it through the rules instead of buying what it suggests blindly ^[16].