When may a court motu proprio dismiss a case?

[2] If for no justifiable cause, the plaintiff fails to appear on the date of the presentation of his evidence in chief on the complaint, or to prosecute his complaint for an unreasonable length of time, or to comply with the Rules of Court or any order of the court (Rule 17, Sec. 3); and
[3] After an examination of the allegations in the complaint and such evidence attached thereto, the court may dismiss the complaint outright on any of the grounds apparent therefrom.(Rule on Summary Procedure, Sec. 4)