This is the 11761st most frequent Russian word.
заинтересовало
"Заинтересовало" means "interested" or "caught the interest."
'Заинтересовало' is used as the past tense of the verb form 'заинтересовать' to indicate that the subject (the proposal) invoked interest in me.
Меня заинтересовало предложение об обмене опытом.
I was intrigued by the proposal to exchange experiences.
'Заинтересовало' is conjugated to match the feminine singular subject 'идея' and showcases its ability to incite interest.
Эта идея заинтересовала многих участников форума.
This idea intrigued many forum participants.
In the question, 'заинтересовал' is the masculine singular form used to discuss the project engaging someone's interest.