In the intricate world of business development and sales strategy, telemarketing, despite the evolution of digital marketing, still plays a pivotal role. As a blend of marketing and telecommunications, telemarketing is a direct approach involving one-on-one dialogue which can be highly effective in expanding business horizons. But how can one discern the most suitable telemarketing agency that would align with their unique business requirements? The answer lies in asking the right questions.

Firstly, it is essential to understand the experience and expertise of the agency. Probing about their history, depth of experience in your industry, and success stories can give you valuable insights. The longevity of a telemarketing agency is often proportional to its adaptability and resilience, both desirable traits. You should consider asking, "Can you provide an account of your experience in my business vertical?"

The dialectics of telemarketing success are not limited to just the experience of the agency, but also depend on the competence of the individual telemarketers. Therefore, understanding their recruitment process, training protocols, and turnover rate is crucial. This might lead you to put forth questions like, "How do you source and train your telemarketers?", and, "What is your staff turnover rate?"

Any discourse on telemarketing would be incomplete without discussing lead generation, the lifeblood of sales cycles. The quality of leads generated can determine the success rate of achieving sales conversions. Therefore, it is not only relevant but also necessary to ask, "What strategies do you employ for lead generation, and how do you ensure quality control?"

In this era of data-driven decision making, the measure of success is not just the final sales conversion, but also the various metrics that lead to it. Understanding how a telemarketing agency tracks these metrics can be enlightening. Ask them, "What Key Performance Indicators (KPIs) do you track and how are they reported to the client?"

In the grand scheme of telemarketing, compliance with legal norms is of paramount importance. With laws such as the Telephone Consumer Protection Act (TCPA) in the US, and the Privacy and Electronic Communications Regulations (PECR) in the UK, non-compliance can lead to substantial fines. Therefore, it is wise to question, "How do you ensure your telemarketing activities are compliant with relevant regulations?"

Lastly, it's prudent to understand the pricing structure of the agency. Aligning your budgetary constraints with the agency's pricing model can prevent unexpected expenses. Ask them, "What is your pricing structure? Is it flexible based on my needs and budget?"

To juxtapose, choosing a telemarketing agency is akin to selecting a suit. You would want it to fit perfectly, reflecting your style, and serving the purpose for which it was chosen. There is no one-size-fits-all. The answers to these questions, when synthesized holistically, can guide you to make an informed decision, enabling you to partner with a telemarketing agency that resonates with your business objectives.

Remember, the purpose of these questions is to facilitate dialogues that would help you peek behind the facade of the agency’s marketing rhetoric and assess the realities. The key is to be discerning and critical in your evaluation, comparing and contrasting the answers, and aligning them with your business needs. A perfect fit may be elusive, but the pursuit of it can lead you to a partner that can drive your business towards growth and success.