In other words, a “better” lawyer can win more often because he chooses better cases to take to court and rejects or resolves those with the least chance of winning.
In fact, there is criticism of legal education, in general, for focusing unduly on appellate courts, which are far removed from the daily work of most lawyers.Hanretty, Chris, “Attorneys rankings either don't matter for litigation outcomes or are redundant” (201, 23 International Journal of the Legal Profession, 185, 195Crossref/Google Scholar). However, individual attorneys get unusual results, and more experienced attorneys sometimes have a lower success rate in court, perhaps because they handle more complex cases. Keep in mind that quality control appointments in Canada have been periodically suspended at the federal and provincial levels, making them questionable as a stable measure of the “quality” of lawyers.
It's also possible that some attorneys handle challenging cases precisely because they're challenging. One firm had 200 lawyers (Dentons Rodyk & Davidson LLP), while the next largest firm had 100 lawyers (Shook Lin & Bok LLP). A 19th-century story about Judge Wightman describes how he met with a member of a jury and asked him what the man thought of the lawyers he had seen. The focus is on whether there is a correlation between the different indicators of the quality of lawyers (the size of the firm, the professional situation, the years of experience, etc.) and real success in court.
See Teitelbaum, Lee E., “The Advocate's Role in the Legal System” (197 6 New Mexico Law Review 1, 18Google Scholar) (arguing that the lawyer's functions should not be considered in tension, but in the context of his function of defending the client's interests). See, for example, Padilla v. Commonwealth of Kentucky, 559 US 356 (20) (attorney assistance was proven ineffective in a case where a lawyer wrongly informed a non-citizen defendant that pleading guilty would not lead to deportation).