A landing page is a page with one job: get the person who arrives to take one action. It's not your site's home page, which has ten links and no direction. It's a one-way path: a problem, a promise, a single possible action. Everything else distracts, so it comes off.
The difference from the brochure site is the whole point. The brochure tells people who you are: about us, services, contact. The landing does one thing: convert the traffic you send it. Send your campaigns to the home page and you're walking people into a lobby full of doors. Send them to a landing and you're walking them down a corridor with one exit.
The anatomy of a landing that converts, top to bottom: a headline that names the visitor's problem, not your product's name. A subhead that promises the result. Concrete proof, a number, a case, a real review. A single call to action, repeated. And zero navigation menu, because every extra link is a fire exit out of your funnel.
The element that moves the numbers most is the entry offer. Asking a stranger to 'book a consultation' converts poorly. Lowering the barrier with a quiz, a guide or a free analysis converts far better. For RicorsoCartelle.it the landing didn't ask for the call: it offered a free 2-minute check. Result: 1,987 registrations on €1,322 of spend.
The second factor is match between ad and page. If the ad promises 'find out if your tax notice can be challenged' and the page talks about something else, the visitor bounces. Match means the first line of the landing continues the sentence the ad started. It sounds obvious, but it's where half of paid traffic gets lost.
What not to do: fill the page with paragraphs, add more than one different call to action, ask for ten form fields. Every bit of friction is a percentage of conversion gone. A landing is subtraction, not addition.
If you want to know whether your system's problem is the landing or another layer, this site has a free 2-minute audit that analyzes the 4 parts of your acquisition engine and tells you which one to start from.