What common types of doubts do people have about sources?

People often question the credibility of sources based on their authorship, seeking to know the qualifications and expertise of the individuals or organizations behind the information. They may also doubt the reliability of the data presented, particularly if it appears biased or lacks proper citations. Additionally, the timeliness of the information can raise concerns, as outdated sources may not reflect current understanding or developments. Lastly, potential conflicts of interest or funding sources can lead to skepticism regarding the objectivity of the content.