Most of them are not ABET accredited. Class sizes are large.
In defense of this practice, how do you handle students that finished undergraduate 5, 10, 15 years ago? If you do much gating, there are not enough students.
Because domestic undergrads applying to a research-oriented grad program are advised to apply directly to a PhD program.
MS/MA programs are expected to remediate deficiencies at the undergrad level, and most undergrads will take 1st year MS/MA classes as part of their senior year doing a bachelors. Alternatively, the MS/MA is awarded if a PhD candidate failed Quals.
Outside the US, the expected path is BA/BSc/BEng/BTech to MS/MA/MTech/MPhil to PhD.
In the US, the expected path is SB/AB to PhD and MS/MA if you fail quals or are looking for a professional program to remediate coursework deficiencies.