What are the pros and cons of switching to an IaaS provider?

Here is the logic I generally recommend:

If you can buy SaaS from a credible vendor, do that.

If you cannot, use the highest-order cloud platform services you can. Serverless is usually the best option unless you are at massive scale.

Use IaaS as a last resort, only when you cannot buy SaaS or use cloud-native platform tech. Note that IaaS is really just “hosting” repackaged as cloud in most cases, and is the least cost-efficient and operationally-efficient way to use cloud platforms. It is very, very expensive unless it is implemented and operated competently. Lift-and-shift is the worst case scenario and yields the most expensive and least beneficial outcomes.

Never buy physical hardware or infrastructure unless you have a unique corner case that literally requires it - for example, a remote location with poor Internet connectivity, truly massive datasets that are too expensive to work with in public cloud, or mining crypto.

Pros: 
1. Cost savings: IaaS provides a range of services at a lower cost than traditional IT services, allowing organizations to save on costs associated with infrastructure, hardware, software, and operations. 
2. Scalability: IaaS providers allow businesses to scale up or down quickly as their needs change, enabling them to respond to market demands quickly. 
3. Flexibility: IaaS providers allow businesses to customize their services to their particular needs, allowing them to tailor their solutions to their specific requirements. 
4. Security: IaaS providers have comprehensive security protocols and measures in place, allowing businesses to protect their data and systems from potential threats. 

Cons: 
1. Lack of control: IaaS providers manage the infrastructure, hardware, and software, meaning businesses have less control over their IT solutions than if they were to manage them in-house. 
2. Vendor lock-in: IaaS providers may require businesses to use their services exclusively, making it difficult to switch to another provider if needed. 
3. Reliability: IaaS providers are dependent on the internet for their services, meaning businesses may experience disruption in service if the internet connection is poor. 
4. Compliance: IaaS providers may not meet certain regulatory or compliance requirements, making it difficult for businesses to use them in certain industries or applications.