Proxycurl scrapes public Linkedin profiles in real-time and on-demand. Web scraping takes time, and on average. Every API Request dispatches a real-time job to scrape a profile. Because each API request is a job to scrape a profile live, it takes about 5-6 seconds to complete and the API to return results.
LinkDB is a database of pre-crawled profiles that you can use to get profiles close to instantly with an SQL query if you require immediate results.