Hello all, new member but an old owner of 2014 mt 07.

My mt 07 decided to develop a problem on start.
For the past week, the engine has been increasingly difficult to start. It takes about 3 seconds / 3 turnovers to turn it on, but even then just barely. But it has been getting worse and worse for the past 4 days. Warm or cold engine - same story.
When it runs, it runs well, does not stall. No flashing dashboard or fading electronics. The ignition switch starts the procedure well.
The battery has a full charge, taken it out and tested it. Even plugged it into a dumb charger to make sure it got full. This did not solve anything.

My motorcycle knowledge is quite basic.
The battery was full when I took it out, therefore, the alternator should be ok.
Battery seems to be alright and working.
Fuel pump must be alright as the motor runs normally.
Starter motor?

I am out of my depth and am just waiting until one day in the morning it won't start.

Thanks for your help and (possibly cheap) ideas and solutions!