High spam reports can lead to several negative outcomes:
1. Decreased Deliverability: Your emails are more likely to end up in the spam folder. 2. Reduced Engagement: Lower open and click-through rates due to poor deliverability. 3. Damage to Sender Reputation: ESPs may flag your domain as a high-risk sender. 4. Potential Blacklisting: Severe cases can result in your domain being blacklisted by multiple ESPs.