Last login date powershell script vs Active/Inactive Dashboard Report

Hi, I am new to Office365 online email service. So just finding my way around the gui and

powershell tool.

I have run the active/inactive email boxes dashboard report and took a note of the stats.

I also ran lastlogin date command in PowerShell and saved output to a CSV file.

eg. "Get-mailbox -resultsize unlimited| Get-MailboxStatistics | select displayname, lastlogontime"

What I am noticing is that the dashboard report stats do not resemble the powerscript output at all.

 The dashboard suggest more people not accessing their mailbox yet the PowerShell command output suggest more people accessing the mail box.

Can anybody help me understand why - which output do I take as accurate.

I would say not everybody will be accessing the mailbox in the same fashion, some use the online portal through a PC browser other may use mail client on mobile phone. Does that affect the stats.

thanks

S.