Cloudflare are a global CDN (Content Delivery Network) and DNS service provider based in San Francisco, California. They offer services to improve website performance, security, and reliability by caching content, encrypting data, and protecting against DDoS attacks.

Why Cloudflare Outages Affect Other Websites

1. Single Point of Failure: When Cloudflare experiences an outage, it affects all websites using their service because they handle the requests for a significant number of domains.
2. Complex Infrastructure: The complexity of Cloudflare’s infrastructure can lead to widespread issues if something goes wrong with their backend systems or network components.

Why Cloudflare Can Be Bad for Customer Experience

1. Down Time and Performance Issues: Frequent outages can disrupt user access, leading to frustration and lost business.
2. Increased Latency: While they aim to reduce latency, poorly configured settings or mismanaged cache policies can actually increase load times.
3. Pick the pictures, enter the numbers, and annoying captchas frustrate customers and turn away potential business.
4. Complexity in Setup and Maintenance: Cloudflare’s advanced features often require significant setup and ongoing management, which can be overwhelming for small businesses.

Understanding Common Cloudflare Errors

Cloudflare errors can appear when there are issues with your site's connection to the internet or specific configuration problems:

• Cloudflare: Error 1012 - DNS Configuration: This means that the domain is not correctly configured in Cloudflare’s system, leading to a failed request.
• Cloudflare: Error 1014 - Rate Limit Exceeded: Occurs when there are too many requests from your IP address. You might need to adjust your settings or contact support.
• Cloudflare: Error 500 (or just "Error"): Cloudflare is broken again, you will simply have to wait for it to be fixed. 
• Host: Error 502 Bad Gateway: This is not specific to Cloudflare but can occur if the server requested by the gateway returns an error.

Alternatives to Cloudflare

1. AWS CloudFront - A global content delivery network that integrates seamlessly with Amazon Web Services (AWS).
2. Akamai - Another leading CDN service known for its robust security features.
3. Google Cloud CDN - Offers excellent performance and scalability, ideal for large-scale applications.

By far the best option is to roll your own CDN, which is a fairly simple affair and provides complete control over a system that can scale with your needs. This won't be free, but it will keep working even when Cloudflare doesn't.