Reddit's /r/bonsai classifies its skill tiers partially by the number of trees one has killed:
I'm just wondering, how accurate do you all think this is? The reason I ask is that I'm a super new beginner, and wondering if it's common to kill over 10 trees in your first 4-10 years of experience. I'm pretty sure one of my first purchases, a Jaqueline Hillier elm, is on death's door after I bare rooted it last month in a workshop and failed to keep it sufficiently watered. All of its leaves are really crispy and its not pushing out any new growth. I'm having a hard time knowing I could have done more to save it- feels like such a shame and this is probably going to get me laughed at but loss of a beautiful life? I guess I could just use some reassurance that this is all part of the learning process and I'm not totally incompetent.
- Beginner: zero to four years experience, owns 1-5 trees, killed a tree in the past
- Intermediate: four to ten years experience, owns 15+ trees, has been on courses, killed over 10 trees.
- Experienced/advanced: well over ten years experience, owns 30+ trees, attended multiple courses - may even teach, has exhibited trees, won awards and has killed dozens of trees.
- Master: probably 15years+ experience but professionally trained, potentially owns or works with hundreds of trees of significant value, probably works professionally in bonsai - lecturing and workshops, may have apprenticeship in bonsai in Japan.