Online marketing professionals' perceptions about the challenges have got huge importance on marketing campaigns and conversion rates. Online marketing professionals' effective digital marketing strategies are crucial for businesses and clients to grow. However, marketers are facing several challenges in optimizing campaigns, and how they perceive them can affect the whole outcome of the campaigns, the clients' success, as well as certain markets. Understanding their perceptions is important for developing effective strategies and improving conversion rates. Therefore, this research aims to explore the perceptions of challenges that marketers are facing when it comes to optimizing online marketing campaigns. The data for this qualitative project was collected through a total of 9 interviews, of which 4 were in-depth, and 5 were conducted to support or refute the discovered themes. All of the interviewees are highly-experienced online marketing professionals who are currently working in this field. The findings of this study are divided into 5 themes, and each theme has a challenge and a solution part. Marketing professionals can perceive the challenges along these 5 themes when optimizing campaigns to improve conversions. These 5 themes cover: (1) client communication, (2) applied methods, (3) internal factors, (4) external factors, and (5) timeframe. The marketers perceive the challenges in our studied topic along the 5 identified factors below: (1) do not understand each other with the client, (2) there is no clear idea about what kind of methods can work, (3) they have a limited effect on the company's internal factors, (4) external factors cause an anomaly, (5) lack of long-term goals. They can overcome these with client-centric communication, clear ideas, a well-thought-out decision-making approach, market-appropriate strategies, and long-term goals.