The 5 most common SEO issues found were:

• 70% of agencies had a poor page speed- the average score given was 41
• 63% of agencies had a lack of internal linking
• 57% of agencies had undesirable pages indexed by Google.
• 52% of agencies had pages containing thin content.
• 47% of agencies had pages poorly optimized for keywords

Other honorable mentions, so to speak, include:

• 33% of agencies have a poor backlink profile.
• 27% of the firms were revealed to have copied content from other parts of the web.
• 20% of digital marketing agencies had poor meta titles (especially for service landing pages).
• 20% of agencies hadn’t updated their blog in over 6 months.
• 17% of agencies had no ‘about us’ page.

After analyzing all the mistakes made by agencies, the study included a brief section on the things they’re doing well.

Agencies are doing exceptionally well when it comes to E-A-T, the study finds. That assessment is based on the following factors:

• 100% had a marketing blog.
• 100% had HTTPS.
• 29 of the 30 agencies had a social media presence.
• 100% had displayed their contact information.
• 83% had an “about” or “meet the team” page.

For further analysis of these findings, read the full study here, Story by Search Engine Journal