Not all players will pass the WCAA Initial Eligibility Clearinghouse requirements. What that means is that for DI and DII recruits, they must meet both GPA and SAT score requirements. In DI and DII, the requirements are on a sliding scale, the lower the GPA, the higher the SAT score requirement. To play at DIII, the recruit must only have a high school GPA of 2.0 or higher.
If a recruit does not qualify, he may or may not still attend your school as they have to pay their own way the first year. They can not be on scholarship and they can not practice (although they will reserve a scholarship for the next season). At DI schools, the player will only have 3 years of eligibility (depending on their collegiate gpa, they may be granted a 4th year of eligibility if they maintain a 2.7 cumulative GPA or higher) - in both situations, if they choose to play their 4 year of eligibility they will be playing as 5th year seniors. At DII schools, the player will have 4 years of eligibility. In both situations, they will be eligible to play beginning with their sophomore year, assuming they have a cumulative GPA of 2.0 or higher after their freshman year.
A recruits profile (see image) will show if they are eligible or not according to the Clearinghouse requirements - keep in mind that the Clearinghouse only governs DI and DII schools. A player who is listed as ineligible may still be eligible to play immediately in DIII. Recruits who are not eligible will be taking the SAT throughout the season leading up to the next recruiting period. If you are watching that recruit, you will be notified by your assistant coach if he becomes eligible.