19th June, England v South Africa, 09:30 GMT
He more than doubled his previous best effort to lead his side to stumps on 564 for three, replying to Bangladesh's 387, but feels he could have scored more runs.
Going into the fourth day, West Indies, who lead the series 1-0, lead by 177 runs and bet365 make them 2/7 to win the match, with the draw 12/5 and a Bangladesh win 80/1.
"I’m definitely very disappointed that I did not pass 300, but a double-century is a double-century, and it’s a big milestone, so I guess I will have to allow it to sink in and enjoy the achievement," Samuels said of his 455-ball knock.
"To be honest, if I did not get out, I would have been waiting for the spinners to come back on to bowl. The ball was still new and it’s still a slow surface, and I would have been hitting sixes for the rest of the evening.
"I said before the series I wanted to score a few more international hundreds this year and so this would count as two in my mind, but I am looking forward to the One-Day Internationals to follow, and I’m sure everyone will enjoy watching."
He has enjoyed an outstanding 2012 with the bat and has now scored 866 runs at an average of 86.60 in seven matches since the turn of the year.
"My motivation is my family, my children, and being able to value life more," he said. "I have continued to work hard and my work ethic is different, I’m eating right, staying fit and so all of this hard work is bearing fruit for me right now.
"After batting for so long, my body is still feeling good. All the work that I have put in to preparation, being on the field, batting, bowling and fielding, for hours is not a challenge for my body.
"The way Bangladesh have played the game, it’s a slow pitch and they have placed a number of fielders on the boundary and they were tempting me to score over the top consistently," he added.
"When I slowed down, I was just playing smart cricket because there were a number of singles that were there to be taken and I didn’t mind doing this until the fielders came closer and gave me the chance to score over the top.
"On these types of pitches, it calls for plenty of patience because you can’t just go out there and drive through the line, so you have to enjoy taking singles until the boundaries come, so you have to wait on the bad balls and try to rotate the strike as much as possible."
Samuels believes there is still enough time left in the game for the West Indies to win it and to do so they will have to use conditions to put Bangladesh under pressure when they bat again.
"The pitch is wearing now, so there is still something there for the bowlers. Look at the delivery that got me out and there were a few others in between.
"When you bowl the ‘effort ball’, you can get something out of the pitch. The ball is stopping and it is difficult to play your strokes, so it won’t be easy to score runs."
© Cricket World 2012
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