The premise that fast failures make US startups a better bet than those in the UK needs further clarification and substantiation. While the concept of failing fast and learning from failures is often associated with Silicon Valley and entrepreneurship in the US, the success of startups depends on various factors, including market conditions, support ecosystems, and cultural attitudes towards failure.

Here are a few reasons why fast failures alone may not necessarily make US startups better bets than those in the UK:

1. Market Differences: The US and UK have distinct market sizes, consumer preferences, and regulatory environments. These factors can significantly influence the success of startups, regardless of their approach to failures.

2. Risk Appetite and Failure Tolerance: The perception and acceptance of failure vary among cultures. While the "fail fast, fail often" mindset is celebrated in some US startup hubs, other countries may have different societal attitudes toward failure, which could impact the learning process and long-term success.

3. Startup Support Ecosystems: The availability of resources, mentors, and funding can play a crucial role in the success of startups. The strength and maturity of the startup support ecosystems in both the US and the UK can impact the ability of startups to recover from failures and pivot successfully.

4. Industry-specific Factors: Certain industries or sectors may have unique challenges and opportunities in different countries, which can influence the success of startups regardless of their approach to failure.

5. Team Quality and Execution: The quality of the founding team and their ability to execute their vision are critical factors in startup success. While learning from failures can be beneficial, the competence of the team and the strategies they implement are ultimately more important than the number of failures they face.

6. Access to Capital: The availability of capital and the funding environment can influence a startup's ability to recover from failures and continue experimenting. The accessibility of funding in the US, particularly for early-stage startups, is often cited as an advantage, but the UK also has a growing ecosystem of investors supporting innovative startups.

7. Customer Feedback and Market Validation: Startups that effectively listen to customer feedback and pivot based on market validation can increase their chances of success, irrespective of their geographic location.

8. Global Competition: Startups in both the US and the UK face global competition. Success often depends on how effectively startups understand and address the broader global market, rather than merely excelling in their domestic markets.

In summary, while fast failures can provide valuable learning opportunities for startups, the success of startups based on this aspect alone is multifaceted and influenced by various factors. It's important to recognize that the choice between US and UK startups should be based on a comprehensive analysis of these factors rather than a limited focus on the speed of failures.