What does it mean if I can perform 25% more reps on my 2nd working set of tricep exercises than my 1st working set of the same weight? And does it mean I'm failing my warmup sets or something else?
(Age 40, male, 260 pounds, lifting diligently for just under a year)
For background, here is my post 23 days ago where I struggled to find a single tricep exercise that successfully targeted my tricep muscles. Thankfully I got good answers and played around at ridiculously light weights at high volume focusing on form and "flexing" my tricep during every rep especially during lockout to help my brain learn how to recruit tricep motor units. As a result, the most successful tricep exercise that "works" for me and isn't constrained by my limitations is assisted dips while keeping the body upright.
This makes me feel very fortunate because many fitness youtubers (Jeff Nippard and 2-3 others) argue that dips are arguably the best single tricep exercise followed closely by overhead cable tricep extensions, which I still struggle with but is a top priority that I'm focusing on for the next 3-4 weeks incorporating into my push day. The only other tricep exercise I feel I'm able to perform correctly and with acceptable form and good tricep targeting is the Close-Grip (slightly Incline) Bench Press however I struggle immensely with my elbows wanting to flare out and I have difficulty keeping them tucked in, especially my ~5% weaker left side elbow which brings me to my next question.
##Question #2
If I can't do more than 6-7 good reps in clean form (with about 4-6 more in shoddy form) of the Close-Grip bench press, does this mean I need to lower the weight until I can do 12 reps in good form? Or does it mean I need to stop when my form gets bad after the 7th rep and compensate by doing more volume by doing more sets? My goal is functional tricep strength and/or hypertrophy but I would slightly prefer strength by a tiny margin. (as an aside, ai says 30-45 degree elbow flare is fine apparently?)
Primary question (in title): What does it mean if I can perform 25% more reps on my 2nd working set of tricep exercises than my 1st working set of the same weight? And does it mean I'm failing my warmup sets or something else? My typical warmup routine is 5 minutes on treadmill at 3mph or 4.8kmh, 2 minutes of "elbow circles" (due to some men having proclivity for elbow pain when working triceps), and 1 warmup set of 40% - 50% weight of my working set for about 10 reps.

