usability - Whom should we design for? Early Adopters or Late Adopters?

If we categorize the users as "Early Adopters" and "Late Adopters", whom should we design for?

The categorization is not just based on their age, but their capabilities or interest towards adopting the new technologies into their lifestyle as soon as they are available.

The Early Adopters (20%) percentage is much lesser than the Late Adopters (80%).

I would be really thankful to you if you can share your thoughts and research in this area. Thank you.

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Update (real scenario): I have built a clickable prototype and doing usability testing:

1. I have created a Datagrid which is same as Dropbox Datagrid.


2. For multi-row selection, I haven't used any checkboxes.


3. Ctrl + click selects random rows and Shift + click selects rows continuously

Now, the problem is, very few users are able to select the rows using the keyboard and mouse (random or continuous), but the majority of the users are asking for checkboxes (the traditional way).

If we consider the former as Early Adopters and latter as Late Adopters? whom should we go with in this case?

I am not against using checkboxes, but despite providing coach marks, education, hints, etc., not sure why the majority of the users want to go with traditional way?