I've always been obsessed with Ben Horowitz' timeless Good Product Manager, Bad Product Manager essay.
Here's my take on a marketing version:
Good marketers can communicate a clear narrative of how marketing drives revenue. Bad marketers resemble an internal content agency, because marketing is "where blog posts come from."
Good marketers build a strategy based on the business model and the target customer. Bad marketers have a list of ideas to try, based on reading case studies, listening to podcasts and from the input of other teams.
Good marketers recognize that marketing is an amplifying function. Bad marketers don't know when to change jobs.
Good marketers have a list of priorities, ordered by potential impact on the business. Good marketers are high output managers of their teams and the teams around them. Bad marketers are experts at performing low-value activities with perfect execution. Bad marketers get stuck on t-shirt designs.
Good marketers are great at marketing their marketing. Bad marketers lament that nobody respects marketing.
Good marketers have a developed opinion for what "marketing" should look, feel and sound like, and why. Bad marketers have no idea what is important to the customer, so they get overruled by outspoken non-marketers inside their company.
Good marketers think about organizations in terms of incentives and alignment. Bad marketers assume that Sales, Product or Engineering are being intentionally obtuse because they're just lazy.
Good marketers know how to get more budget from their boss or someone in finance. Bad marketers don't know how to explain marketing impact in non-marketing terms.
Good marketers are accountable to marketing goals and metrics. Missed goals trigger an objective diagnosis which provide clarity and potential paths to success. Bad marketers don't have any goals. If they have goals, and they miss them, it's because of "seasonality" or because the data is unreliable or because of competition. Bad marketers start by assuming they'll miss goals.
Good marketers have multiple ways of benchmarking against the competitive landscape. Bad marketers don't know any marketers other than the ones that work in their company.
Good marketers don't get trapped by the sunk cost fallacy. Bad marketers don't understand opportunity costs.
Good marketers recognize their own strengths and how they deliver value. Bad marketers feel anxious that they don't know how to code.
Good marketers know their weaknesses intimately and know how to compensate for them. Bad marketers are emotional about admitting weaknesses.
Good marketers actively seek out context and understanding the company strategy. Bad marketers default to blaming management for giving unclear direction. Bad marketers enjoy - and have a habit of - commiserating with colleagues.
If you liked this, you may also enjoy Junior Marketers vs Senior Marketers, another blog post that is basically me yelling at myself for poor decisions I've made in the past :-)