Professional development and learning new information and skills is, of itself, of value as is the mindset of ‘lifelong learning’. As they say ‘Something learnt is something gained’!

That said – whether other people see the training / course as beneficial, from an employability perspective, depends on these key factors:

• Relevance to the job or employment opportunity. It needs to relate to the job, either in an essential form or as a value-add, or at least demonstrate a characteristic of eagerness to learn.
• Phase of a person’s career – immediately post school, graduate / early career or well experienced? Does the course align with expectations of capability, knowledge and maturity?
• Seniority or complexity of role – graduate and post graduate qualifications are generally expected for people applying for senior roles, with wide ranging responsibilities and accountabilities or highly technical roles. Often the more senior the role the higher the level of qualification.
• Role specialisation / technical requirements – eg need a license to practice (eg electrician, plumber) or accreditation / certificate of some kind (eg responsible service of alcohol (RSO), first aid, working with children / vulnerable people, or to provide training and development to adults). 
• Credibility of training provider – is the certificate worth the paper it is written on / the time spent doing it? Many employers / recruiters look for qualifications through Registered Training providers, tertiary institutions or accredited specialist providers eg Australian Institute of Company Directors (AICD) or Governor Leadership Foundation (GLF). These will have more sway with employers / recruiters than obscure providers with minimal public awareness or web presence. 
• Free online courses through LinkedIn will likely have little merit with discerning employers / recruiters, particularly where competition for jobs is intense – unless it’s seen as a value-add for an early or transitioning career applicant who can sell its benefits and differentiate themselves from the field!