Fair enough, but this assumes Danny makes the perfect selections in X future drafts. He did, however, draft Melo over Ezeli (even Perry), traded Books for JuJuanna, and had the benefit of seeing the progress Rondo and Perk under the tutelage of 3 HOFers.
I don't think the OP is assuming this at all. He breaks down the percentages of good players that fell to these spots and aligns them with the odds that we will draft contributers of varying levels (based on the average GM). If DA is better than average, then his odds of finding "players" are a bit higher. If DA is below average, then they are a bit lower.
Yeah I'm not assuming Danny is a great drafter, although if you read this whole post you'll find out it wouldn't be wrong to do so. I was giving averages like droopdog said.
It's easy to look at Danny's misses and say that he might miss in the future. Let's take a look at DA's track record as Celtic's GM (on a scale from Kahn to 10). I don't like to focus on who a GM missed. It isn't a very good way to judge them because the error rate is so high. Every GM has missed out on a great player, even the lauded Sam Presti. (Presti missed on Marc Gasol in 2007, like everyone, along with all of the same smaller misses Ainge had in 2008, for example)
[Sticking to the 1st round as the 2nd round is essentially a crap shoot and I have limited time]
2003: Danny's first draft
Traded Troy Bell (#16) and Dahntay Jones (20) for Marcus Banks (#13) and Kendrick Perkins (#27).
While it's easy to say "well Ainge whiffed on David West, Leandro Barbosa, and Boris Diaw" it's not a great method of evaluating any GM. At least 10 GMs whiffed on David West (Rick Sund of Seattle did it twice). Ainge drafted a couple of guys and turned them into Marcus Banks (bust) and Kendrick Perkins (NBA role player). So that is 2 picks and 1 hit. 50% so far. Also Perkins was moved for Jeff Green, a #5 overall pick.
2004: Ainge's (second?) best draft
3 first round picks, 3 really good players. Jefferson is a fringe all-star candidate. Allen is a top NBA perimeter defender and West is a talented screw-up. Can't argue with any of these picks, especially considering this was the draft that set us up to get KG and Ray. I'd call this 3/3 but I could see an argument for 2/3 considering West is a headcase. I'd argue West helped us get Ray but I can see both sides.
2005: Slump!
This draft represents 'bad Danny' about as well as any. Ainge likes to chance on athleticism a bit. Here is the argument I'll make in his defense, not statistically but as an aside. Green was a bust, I concede that, but there wasn't a lot in this draft after Danny Granger came off the board. Gomes was also a really nice grab at #50 and ended up being a part in the KG trade. So while this was a bad draft for Danny, it wasn't a set back in my eyes.
2006: Why Danny is great
This draft was mediocre. It was a low-talent, bad odds draft. The 2013 draft will look at lot like this in 5 years I expect. 3-5 guys who are starters, 2-all stars then dregs. Ainge traded Foye and some stuff for Telfair. He also traded a future 1st (Rudy Fernandez) for the rights to Rajon Rondo. Oh and he turned a 2nd rounder into Leon Powe. Ainge went in to this draft with the 7th overall pick (Foye) and walked away with Rondo, Telfair and Leon Powe. Talk about turning nothing into a big something.
2007: Tanking for nothing...or something.
This was a trade draft for Ainge as the lotto didn't go our way. Ainge picked up Jeff Green parlaying that into Ray Allen, and along with more GM gymnastics, banner #18. Oh and as a side note he got Jeff Green back in 2011 for a previous #27 overall pick, Kendrick Perkins.
2008: We won, so we get last pick
This might have been Ainge's worst draft to date. There were 5-6 players worth drafting at pick #30. This is a draft I can see people criticizing Ainge for his misses. Pekovic, Jordan, Asik, LRMM and even Dragic. Again I don't think this is a good method for evaluating a GM but I can see how one might be tempted to use it, especially because we desperately needed a healthy center for the next 4 years and there are 3 there. Oh well everyone lays an egg here and there. [See the aforementioned Sam Presti comment]
2009: No first rounder pick (trade to MIN to KG)
Minny picked Wayne Ellington. The best player left was probably Danny Green. Worth it.
2010: Back on the horse
Ainge knocked this one out of the park. I know AB isn't a superstar but just look at the 11 picks in the first round after AB and then the 30 picks after that. There is no one. This was a huge, I repeat, huge pick. Just google for "Bradley blocks Wade".
2011: The trade that wasn't
We traded Brooks for Johnson and a 2014 2nd round pick. We've since traded that 2nd rounder to move up for Olynyk and reacquired Brooks. No harm no foul? Johnson was a bust.
2012: Draft a big man
We were gifted Sullinger on a draft day slide and we took Melo as a Perkins-style project. Not a terrible draft. Too early to tell really. I'm personally pretty high on Sully.
2013: KO!
Also too early. But if summer league is any indication of his success...it's not but hey I like to stay positive
So some quick summation:
Ainge has made 12 first round draft choices. Not all of them played for us. Of the 12, I'd say 7 of them have had productive NBA careers. That is a 58% success rate. Add in that he's made trades to keep us competitive over the last 6 seasons and that he traded for our current franchise player, former franchise player and we have 9 first round picks in the next 5 years...I have nothing but faith in Danny Ainge.
Here are some links for good reads that I used in compiling this:
Danny Draft HistoryGM RankingsBOS Draft History