You've heard admonitions like this before, of course, in reference to the need to steer past mere baseline competence from a contracting third party when what you truly need is high-level performance from an individual or business entity.
To wit: You wouldn't seek out a general practitioner to perform brain surgery. You wouldn't hire an entry-level cook to cater your child's wedding. You wouldn't entrust your life savings to an adviser you just met who promises you outsized returns, so ...
... why would you retain an attorney without appeals-related acumen and experience to represent you in a matter that likely entails potentially adverse consequences of nearly incalculable scope?
A time-honored and bedrock principle of American jurisprudence is that, when one or more material mistakes are committed at trial that result in judicial error (and sometimes the wrongful conviction of a defendant), the adversely affected party has a legal right to appeal.
Although that is critically important, of course, the utility of such an opportunity is only fully realized when appellate legal counsel is up to the task for what is required beyond the initial trial-court stage.
Words can't be minced here: The performance of a criminal defense attorney at the appeals stage is often the central determinant informing a defendant's future.
Proven appellate counsel -- that is, a thoroughly knowledgeable, persuasive and, when necessary, aggressive advocate -- fundamentally understands the need for evidence gathering, trial record review and preserving the right of appeal. An attorney with a demonstrated record of strong advocacy on behalf of clients in appeals cases is necessarily and uniformly focused on court procedures, careful legal drafting and oral argument, and will be ready to pursue an appellate matter before a court of appeals or, alternatively, back in the trial court where a case was first commenced.
Appellate work constitutes a technical and singular realm of law, which can best be entrusted to attorneys and law firms that routinely engage in it.