Medical malpractice insurance acts as a necessary shield protecting healthcare professionals from the potentially devastating costs associated with legal claims. In essence, it is a form of professional liability insurance which provides coverage for alleged errors, omissions, negligence, or any acts leading to injury or harm to a patient. To fully comprehend the intricacies of this insurance, we need to delve into its fundamental aspects and mechanisms.

The question of who needs medical malpractice insurance is relatively straightforward. It is essential for any healthcare professional - be it doctors, dentists, nurses, physical therapists, etc. Essentially, anyone involved in the healthcare chain, whose actions have the potential to directly affect a patient’s wellbeing, should consider procuring a medical malpractice insurance policy.

The "what" pertains to the coverage offered by this type of insurance. This can typically be divided into two categories: claims-made and occurrence policies. Claims-made policies provide coverage for claims made while the policy is active, regardless of when the malpractice incident occurred. Occurrence policies, on the other hand, cover incidents that occurred during the policy period, irrespective of when the claim is made.

Both types of policies have their merits and demerits. Claims-made insurance is generally cheaper and offers flexibility for increased coverage limits over time. However, it necessitates the purchase of "tail coverage" to protect against claims made after the policy is terminated. Occurrence insurance negates the need for tail coverage as it covers any incident occurring during the policy period, but the premiums tend to be higher, and the policy limits remain static.

The “where” aspect pertains to jurisdiction - laws governing malpractice insurance vary by location. Many states in the United States require healthcare providers to carry medical malpractice insurance, while others do not. Thus, the scope of coverage might differ based on the location and local laws.

The “when” can be interpreted in two ways: when to acquire malpractice insurance and when it comes into effect. The ideal time to acquire insurance is before a healthcare professional starts practicing, as this ensures protection right from the first patient interaction. As for when the insurance comes into effect, it depends on the type of policy. Claims-made policies activate when a claim is reported, while occurrence policies respond to claims based on when the incident occurred, not when it was reported.

The “how” aspect revolves around the cost and underwriting process. The cost of insurance is influenced by factors such as the healthcare professional's specialty, location, claim history, and the policy's coverage limits and deductibles. The underwriting process involves a thorough review of these factors and more by the insurance company to determine the risk level and subsequently, the premium cost.

The final and perhaps, the most crucial aspect is the "why". The cost of a lawsuit emanating from medical malpractice can be financially crippling, even if the healthcare provider is found not liable. Legal fees, court costs, settlements, or judgments can run into hundreds of thousands, if not millions, of dollars - costs which can be mitigated with the right malpractice insurance.

In conclusion, medical malpractice insurance serves as a critical safety net for healthcare professionals, providing financial protection and peace of mind. It ensures that they can focus on their primary purpose - providing the best possible care to their patients, without the constant fear of financial ruin due to potential lawsuits. Like any form of insurance, it’s a preventive measure, a strategic feint against the unpredictability inherent in the practice of medicine. The complexities of this type of insurance warrant careful consideration and consultation with a knowledgeable insurance professional.