A paid-search landing page should continue the promise made in the advertisement. When the keyword, ad and page use completely different language or offers, visitors are more likely to leave without taking action.
What to consider
Keep the page focused on one primary goal, provide enough information to build trust and make the form appropriate for the value of the enquiry. Mobile performance is especially important because many paid clicks occur on phones.
Track meaningful conversions and lead quality, not only click-through rate. Campaign optimization should combine advertising data with landing-page and sales outcomes.